HomeMy WebLinkAboutOrdinance No. 6464 CITY OF SPRINGFIELD, OREGON
ORDINANCE NO. 6464 (GENERAL)
AN ORDINANCE AMENDING THE SPRINGFIELD DEVELOPMENT CODE RELATED TO POST-
CONSTRUCTION SITE RUNOFF AND STORMWATER MANAGEMENT FOR NEW
DEVELOPMENT AND REDEVELOPMENT, ADOPTING A SAVINGS CLAUSE AND A
SEVERABILITY CLAUSE, AND PROVIDING AN EFFECTIVE DATE
WHEREAS, the City of Springfield is subject to the National Pollutant Discharge System (NPDES)
Phase II permit regulations for Municipal Separate Storm Sewer Systems (MS4), administered by the
Oregon Department of Environmental Quality (DEQ) via the MS4 Modified General Permit (MS4 Permit),
effective March 1, 2019, as modified March 21, 2021;
WHEREAS, DEQ issued the City of Springfield MS4 Permit on June 1, 2021, and the permit expires
February 28, 2024;
WHEREAS, the MS4 Permit requires the City of Springfield to address six minimum control measures,
including Post-Construction Site Runoff for New Development and Redevelopment;
WHEREAS, the City of Springfield has existing land use regulations for post-construction site runoff
implemented through the Springfield Development Code (SDC), which was originally adopted on May 5,
1986, and has subsequently adopted amendments thereto by ordinance;
WHEREAS, the City Council finds it in the public interest to amend the Springfield Development Code
consistent with the MS4 Permit and ensure that the City can regulate post-construction site runoff for
new development and redevelopment as needed to comply with the MS4 Permit,
WHEREAS, the Springfield and Lane County Planning Commissions conducted a joint public hearing
on the Springfield Development Code amendments on August 1, 2023, which was continued to
September 5, 2023, and forwarded recommendations to the Springfield City Council and Lane County
Board of Commissioners to approve the proposed amendments;
WHEREAS, the Springfield City Council held a joint public hearing with the Lane County Board of
Commissioners on these amendments on November 6, 2023, and is now ready to act based upon the
above recommendations and evidence and testimony already in the record and the evidence and
testimony presented at the joint elected officials' public hearing; and
WHEREAS, timely and sufficient notice of the public hearings have been provided according to SDC
5.1.615, ORS 227.186 ("Ballot Measure 56" notice), and OAR 660-018-0020;
WHEREAS, substantial evidence exists within the record to demonstrate that the Springfield
Development Code amendments meet the requirements of the Springfield Comprehensive Plan, Metro
Plan, Springfield Development Code, Lane Code, and applicable state and local law as described in the
findings attached as Exhibit B,
NOW, THEREFORE, THE COMMON COUNCIL OF THE CITY OF SPRINGFIELD ORDAINS AS FOLLOWS:
Section 1. The Springfield Development Code is amended as provided in Exhibit A, which is
attached hereto and incorporated herein by reference.
Section 2. The findings set forth in Exhibit B are adopted in support of this ordinance.
Section 3. Construction of Ordinance. In amending the Springfield Development Code, it is
not the intent of the City of Springfield to create new land use regulations that give rise to Ballot
Measure 49 claims or similar claims. In the event that a land use regulation amended as described
herein is capable of two interpretations, one which may give rise to a claim for compensation pursuant
to ORS 195.300 to 195.336 or similar claims, and one which does not, the land use regulation must be
interpreted in a way that does not give rise to said claim.
Section 4. Savings Clause. Except as specifically amended herein, the Springfield
Development Code will continue in full force and effect. The prior code and land use regulations
repealed or amended by this Ordinance remain in full force and effect to authorize prosecution of
persons in violation thereof prior to the effective date of this ordinance.
Section 5. Severability Clause. If any section, subsection, sentence, clause, phrase or
portion of this Ordinance is, for any reason, held invalid or unconstitutional by a court of competent
jurisdiction, such portion shall be deemed a separate, distinct and independent provision and such
holding shall not affect the validity of the remaining portion hereof.
Section 6. Effective Date. The effective date of this Ordinance is as provided in the Chapter
IX of the Springfield Charter and Section 2.110 of the Springfield Municipal Code, 30 days from the
date of passage by the Council and approval by the Mayor; or upon the date that an ordinance is
enacted by the Lane County Board of Commissioners approving the same amendments as described in
Section 1 of this Ordinance; or upon acknowledgment of this ordinance under ORS 197.625; whichever
occurs last.
ADOPTED by the Common Council of the City of Springfield this 20 day of November , 2023,
by a vote of 5 for and 0 against. (1 Absent-Blackwell)
APPROVED by the Mayor of the City of Springfield this 20th day of November , 2023.
Mayor
ATTEST:
REVIEWED&APPROVED
AS TO FORM
Ky'i�tLvta�Kra.a�
DATE: � �
City Recorder SPRINGFIELD CITY ATTORNEY'S OFFICE
Ordinance No. 6464
Exhibit A Page 1 of 133
Amendments to the Springfield Development Code to Incorporate
Stormwater Permit Requirements
AMENDMENTS
Various Sections of the Springfield Development Code (SDC) are amended to remove barriers
to Low-Impact Development and define stormwater terms. SDC 4.3.110 has been re-organized
to more closely match the structure and requirements of the MS4 Permit. The proposed
amendments are shown in legislative format (deleted text with strike-thru red font and new text
with double underline red font). For ease of review, this legislative format does not show where
code language was moved from one place to another. Commentary is shown in purple italics
preceding the text to which it is referring.
3.2.450 CI District—Design Standards
Commentary. The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to allow
vegetated stormwater quality features in the landscaping. Consistent with the MS4 Permit,
vegetation may be permitted within structural stormwater controls.
In the Cl District, new buildings; expansions of, or additions to existing buildings; or
improvements to existing fagades that require a building permit shall provide architectural
designs that encourage flexibility and innovation in site planning by complying with the following
on-site design standards:
(B) Landscaping. The following landscaping standards are in addition to standards
specified in SDC 4.4.105:
(1) A minimum of 35 percent of each development area shall be landscaped open
space.
(2) Plants shall be sized to attain 90 percent coverage of required landscape areas
(excluding tree canopies), within 3 years of installation. Plantings of native
species and plant communities shall achieve 90 percent coverage within 5 years
of installation.
(3) At least 10 percent of the interior of a parking lot having 20 or more parking
spaces shall be landscaped. This standard is in addition to any landscaping
setbacks required in SDC 3.2.420.
(4) Natural assets identified in the Gateway Refinement Plan, any other applicable
refinement plan or elsewhere in this Code shall be included in the site design and
protected. Where protection of these natural assets prevents the development of
the site consistent with this Code, the functional equivalent of the natural assts
may be substituted as may be allowed by the City.
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Ordinance No. 6464
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(5) Vegetation within a structural stormwater control that complies with SDC 4.3.110
may be counted toward the minimum landscaping requirements of this section.
3.2.625 Mixed-Use District Development Standards—General.
Commentary: The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to allow
vegetated stormwater quality features in the landscaping. Consistent with the MS4 Permit, the
City must encourage the use of Low Impact Development stormwater facilities. The word "shall'
was replaced with "must'to clarify that the requirements are mandatory.
Mixed-use zoning districts require special attention to building design because of the intermixing
of land uses and higher intensity of development that can occur in these areas. The standards
below implement commonly accepted design principles with the goal to achieve more attractive,
functional and pedestrian oriented design. Not every case and circumstance is anticipated by
these standards, nor is it the goal of this section to prescribe every design detail of
development. It is expected that the Springfield development community will apply their own
design creativity to build on these principles and create attractive, livable, and viable projects.
The standards below provide an objective framework for achieving the desired goal of attractive,
pedestrian oriented development. Developers may choose to meet these standards as
prescribed, or they may propose other design ideas which are equal or superior to a particular
standard in meeting the design objectives in subsections (A) through (G), below. Where
developers request an exemption from a stated standard, it is their responsibility to propose an
alternative design and to demonstrate to the Director that it is equal or superior to the stated
standard. The Director has the authority to authorize an exception to these standards and
determine the acceptability of an alternative design the developer proposes. When developers
propose alternative designs that are not acceptable to the Director, they may appeal the
decision as specified in SDC 5.3.115.
(D) Landscaping and Screening.
(1) Intent. Landscaping is intended to compliment built forms within a development
area, softening and providing visual relief and contrast to buildings, sidewalks,
parking lots and provide opportunities for stormwater controls including Low
Impact Development. Trees, as part of a landscaping plan, shall must provide
shade for pedestrian comfort as well. The installation of landscaping sh;;" must
be accomplished in a manner that assures that planted stock receives adequate
irrigation. Screening is intended to compliment a development area by shielding
trash receptacles, storage areas and other unsightly facilities from public view
within the development area.
(a) Mixed-use developments shall must provide landscaping and screening
in accordance with SDC 4-4189 4.4.105 and 4.4.110 and the following
standards:
(b) Street trees ha#-must be required consistent with SDC 4.2.140. Species
be compatible with the design features specified in subsection
(G), below and provide continuity with nearby landscaping. The
Director may grant a 1-for-1 reduction in the number of street trees
required when a development preserves healthy, mature trees located
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Ordinance No. 6464
Exhibit A Page 3 of 133
within 10 feet of the sidewalk. Required street trees shall mus be placed
in planter strips between sidewalks and curbs as specified in SDC
4.2.135 and 4.2.140, or in individual tree pits. If individual tree pits are
utilized, each pit shall must be a minimum of 64 square feet per tree, with
a minimum width of 4.5 feet.
(2) Screening of parking areas, drives, mechanical equipment and trash receptacles
shall must meet be as speGifi-d OR SDC 4.4.110. In addition:
(a) No trash receptacles shall be are allowed within the front setback areas
abutting residential districts.
(b) All ground-mounted utility equipment not installed underground shall must
be placed to reduce visual impact or screened with walls or landscaping.
(c) Notwithstanding the timelines specified in SDC 4.4.105, plants ,hall-must
be sized to attain 50 percent coverage in 2 years and 100 percent
coverage in 4 years.
Drinking Water Protection Overlay District
Commentary: The Drinking Water Protection Overlay District was amended with the input of
Springfield Utility Board's Drinking Water Source Protection Coordinator and the City of
Springfield Stormwater Facilities Master Plan (2008). Amendments allow an exception to the
prohibition of dry wells for roof drainage, to prohibit permeable pavements in the 0-1 year time
of travel zone, to clarify an exemption for the use of materials including liquid fuel for generators,
clarified terms throughout 3.3.200, and to prohibit stormwater infiltration in a 100' buffer around
wellheads per guidance from Oregon Health Authority. The applicability of the DWP Overlay
standards in SDC 3.3.235 was revised to clarify that— even when no DWP Overlay permit
application is required—development must comply with any applicable requirements of the
overlay district. For instance, infiltration facilities within 100 feet of a wellhead would be
prohibited even if a development did not otherwise trigger the need for a DWP Overlay permit.
Note: The exception to 3.3.230(B)(3) was revised so that it would not nullify (B)(9)'s regulatory
exemption for emergency generators. The EXCEPTION language was moved to apply under
(B)(3) only. Language was also added to the start of 3.3.235 to clarify that development must
comply with the Drinking Water Protection requirements even if an application isn't required
(e.g., the prohibited uses are still prohibited even if the City is not requiring an application
submittal). Furthermore, the City may seek enforcement if a permitted use starts to use
hazardous materials in a new way that would conflict with the Drinking Water Protection
Overlay.
3.3.220 Time of Travel Zones.
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Ordinance No. 6464
Exhibit A Page 4 of 133
(B) The areas within specified wellhead TOTZ are those drinking water protection areas
certified by the Oregon Health Authority, under the Oregon Administrative Rules
that apply to Oregon's EPA-approved Drinking Water Protection Program, in Oregon
Health Authority Delineation Certification #0002R, Version 2Marc"�
(C) In determining the location of a property within a TOTZ, the following criteria apply:
(1) The Lane County Department of Assessment and Taxation maps shall be
used as a base map with the addition of TOTZ boundaries.
(2) That portion of a tax lot that lies within a TOTZ is governed by the restrictions
applicable to that TOTZ.
(3) Tax lots having parts lying within more than one TOTZ are governed by the
standards of the more restrictive TOTZ.
EXCEPTION: The Director may waive the requirement that the more restrictive
standards apply when all of the following apply:
(a) Storage, use, handling, treatment, and/or production of hazardous or
other materials that pose a risk to groundwater will not take place within
the portion of the tax lot having the more restrictive TOTZ standards; and
(b) Storage, use, handling, treatment, and/or production of hazardous or
other materials that pose a risk to groundwater will not take place within
50 feet of the portion of the tax lot having more restrictive TOTZ
standards; and
(c) The tax lot is 20,000 square feet or larger.
(4) A property owner may request the TOTZ be modified by submitting a Zone
Change application to the City. Any request for modification of the TOTZ shall be
accompanied by certification of the TOTZ as proposed to be modified by the
Oregon Health Authority O+vis+en, under the Administrative Rules that apply to
Oregon's EPA-approved Drinking Water Protection Program. (6238)
3.3.225 Review.
(D) Prior to undertaking an activity covered by SDC 3.3.225(A), the owner or tenant shall
submit a DWP Overlay District Application to the City for review and approval.
Applications shall include the following information:
(1) A Hazardous Material Inventory Statement and a Material Safety Data Sheet for
any or all materials entered in the Statement unless exempted under
SDC 3.3.230. Hazardous material weights shall be converted to volume
measurement for purposes of determining amounts; 10 pounds shall be
considered equal to 1 gallon as specified in Springfield Fire Code 5003.1.2;
(2) A list of the chemicals to be monitored through the analysis of groundwater
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Ordinance No. 6464
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samples and a monitoring schedule if ground water monitoring is anticipated to
be required;
(3) A detailed description of the activities conducted at the facility that involve the
storage, handling, treatment, use or production of hazardous or other materials
that pose a risk to groundwater mateFia;Tin quantities greater than the maximum
allowable amounts as stated in SDC 3.3.235(A);
(4) A description of the primary and any secondary containment devices proposed,
and, if applicable, clearly identified as to whether the devices will drain to the
storm or sanitary sewer;
(5) A proposed Hazardous Material Management Plan for the facility that indicates
procedures to be followed to prevent, control, collect and dispose of any
unauthorized release of a hazardous material;
(6) A description of the procedures for inspection and maintenance of containment
devices and emergency equipment;
(7) A description of the plan for disposition of unused hazardous materials or
hazardous material waste products GyeF the maximum alle able arnG,,r+&
including the type of transportation, and proposed routes.
3.3.230 Exemptions.
This section does not exempt any material or use from Fire Code regulations adopted by the
City.
(A) Exemptions are as specified in this section unless the Director, in consultation with SUB
and Fire/Life Safety, determines that a hazardous material, activity, and/or facility that is
exempt pursuant to this section has a significant or substantial potential to degrade
groundwater quality. Then the Director may require compliance with the requirements of
this section related to that hazardous material, activity_or facility. This determination will
be based upon site and/or chemical-specific data and is aFe eligible for appeal to the
Hearings Officer as specified in SDC 3.3.245.
(B) Unless otherwise provided herein, the following materials are exempt from regulation
hereunder:
(1) Use, storage and handling of specific hazardous materials that do not present a
risk to the aquifer, as determined and listed by the Director in consultation with
SUB, are exempt from all regulation under this section with the exception of the
potential requirement to list these hazardous materials on the Hazardous
Material Inventory Statement as found in the most recent Fire Code regulations
adopted by the City. A Drinking Water Protection_HaZarde, Materials,
Exemption Request may be submitted to the Director for Hazardous Materials
that can be demonstrated to pose no threat to the aquifer. These materials may
be exempted from regulation and_ ad-d-ea d + the Gs,+ The demonstration of no
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Ordinance No. 6464
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threat is the responsibility of the applicant seeking the exemption and will be
subject to review by technical experts.
(2) Hazardous materials offered for sale in their original sealed containers of 5
gallons or less are exempt from the 500-gallon storage limit specified in
SDC 3.3.235(A)(1).
(3) Hazardous materials in fuel tanks and fluid reservoirs including but not limited to
fuel, engine oil, and coolant, which are attached to a private or
commercial motor vehicle and used directly in the motoring operation of that
vehicle, or machinery, ORG1 1doRn 11I+ nn4 IIml49fd 4n. fi lel engine nil and rnnlanf
EXCEPTION: Portable generators are not exempt.
(4) Fuel oil used in existing heating systems.
(5) Emergency use, storage, and handling of hazardous materials by governmental
organizations in the public interest.
(6) Hazardous materials used and stored specifically for water treatment processes
of public water systems and private systems for the same purposes when
approved by the Director.
(7) Hazardous materials contained in properly operating sealed units (including, but
not limited to: transformers, refrigeration units) that are not opened as part of
routine use.
(8) Local natural gas distribution lines.
(9) Fuel for emergency generators located at facilities that provide essential
community services (including, but not limited to: hospitals, fire/life safety, police,
public shelters, wireless telecommunications system (WTS) facilities. and
telephone systems).
(10) Any commonly used office supply—including, but not limited to: correcting fluid
for typewriters, toner for computer printers or cleaners for windows and
bathrooms—where the supplies are purchased off-site for use on-site.
(11) Aggregate quantities equal to or less than 20 gallons of hazardous materials that
do not contain DNAPLs.
EXGEDTIQN I im iod fi ie! fnr geReraterc area nn4 exempt from the rani llatieRs in SDG
3.3.23()(B).
3.3.235 Standards for Hazardous Materials within Time of Travel Zones.
Applications required under SDC 3.3.225(A) must shall comply with the following standards.
Notwithstanding SDC 3.3225(A), development that conflicts with the standards of this section is
prohibited. Where the following standards are more restrictive than the standards of the
Springfield Fire Code, the following standards apply�-will prevail.
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Ordinance No. 6464
Exhibit A Page 7 of 133
(A) Zero to One Year TOTZ Standards.
(1) Within the zero to one year TOTZ, hazardous or other_materials that pose a risk
to groundwater may be stored in aggregate quantities of no more than 500
gallons if in original containers not exceeding 5 gallons* in size. Within that
aggregated 500-gallon inventory, no more than 150 gallons of hazardous or other
materials that pose a risk to groundwater may be on the premises in opened
containers for handling, treatment, use production, or dispensing on site.
Hazardous or other_materials that pose a risk to groundwater are allowed only
upon compliance with containment and safety standards specified by the most
recent Fire Code adopted by the City.
* A waiver of the 5-gallon maximum size may be given by the Director if the
applicant can demonstrate that a larger size container would pose less risk to the
aquifer.
(2) Unless exempted, all hazardous or other materials that pose a risk to
groundwater shall be stored in areas with approved secondary containment in
place (Springfield Fire Code 5002.1 and 5004.2.2).
(3) All new uses of Dense Non-Aqueous Phase Liquids (DNAPLs) are prohibited.
(4) Any change in type of use or an increase in maximum daily inventory quantity of
any DNAPL shall be considered a new use and prohibited.
(5) The following certain types of new facilities or changes in use and/or storage of
hazardous or other materials that pose a risk to groundwater are prohibited:
(a) Underground hazardous material storage facilities;
(b) Hazardous material product pipelines used to transport the hazardous
material off of the tax lot where it is produced or used;
(c) Injection wells;
EXCEPTION: Dry wells for residential roof drainage;
(d) Solid waste landfills and transfer stations;
(e) Fill materials containing hazardous materials;
(f) Land uses and new facilities that will use, store, treat, handle, and/or
produce DNAPLs; and
LgJ Permeable pavements.
(6) Requirements found in Springfield Fire Code 5004.2.2.5 for a monitoring
program and monitoring methods to detect hazardous materials in the secondary
containment system shall be met for all amounts of hazardous or other materials
that pose a risk to groundwater unless exempted.
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Ordinance No. 6464
Exhibit A Page 8 of 133
(7) The following requirements for inspection and record keeping procedures for
monthly in-house inspection and maintenance of containment and emergency
equipment for all amounts of hazardous or other materials that pose a risk to
groundwater shall be met unless exempted: Schedules and procedures for
inspecting safety and monitoring and emergency equipment. The applicant shall
develop and follow a written inspection procedure acceptable to the Director for
inspecting the facility for events or practices which could lead to unauthorized
discharges or-of hazardous materials. An inspection check sheet shall be
developed to be used in conjunction with routine inspections. The check sheet
shall provide for the date, time, and location of inspection; note problems and
dates and times of corrective actions taken; and include the name of the
inspector and the countersignature of the designated safety manager for the
facility.
(8) Application of fertilizers containing nitrates are restricted to no more than the
amount recommended by the Lane County, Oregon State University Extension
Service for turf grass and are prohibited within 100 feet of a wellhead. In no
event shall a single application exceed one half pound per 1,000 square feet of
area per single application or a total yearly application of 5 pounds nitrogen
fertilizer per 1,000 square feet.
(9) Stormwater infiltration facilities are prohibited within 100 feet of a wellhead.
(B) One to Five Year TOTZ Standards.
(1) The storage, handling, treatment, use, application, or production or otherwise
keeping on premises of more than 20 gallons of hazardous or other materials
that pose a risk to groundwater in aggregate quantities not containing DNAPLs
are allowed only upon compliance with containment and safety standards
specified by the most recent Fire Code adopted by the City.
(2) Unless exempted, all hazardous or other materials that pose a risk to
groundwater shall be stored in areas with approved secondary containment in
place (Springfield Fire Code 5002.1 and 5004.2.2).
(3) All new use-uses of DNAPLs are prohibited.
(4) Any change in the type of use or an increase in maximum daily inventory quantity
of any DNAPL is considered a new use and is prohibited.
(5) The following certain types of facilities or changes in chemical use and/or
storage of hazardous or other materials that pose a risk to groundwater
are prohibited:
(a) Hazardous material product pipelines used to transport the
hazardous material off of the tax lot where it is produced or used;
(b) Injection wells;
EXCEPTION: Dry wells for residential roof drainage;
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Ordinance No. 6464
Exhibit A Page 9 of 133
(6) Requirements found in Springfield Fire Code 5004.2.2.5 for a monitoring
program and monitoring methods to detect hazardous ^Fo�Finaterials in the
secondary containment system shall be met for all amounts of hazardous or
other materials that pose a risk to groundwater unless exempted.
(7) The following requirements for inspection and record keeping procedures for
monthly in-house inspection and maintenance of containment and emergency
equipment for all amounts of hazardous or other materials that pose a risk to
groundwater shall be met unless exempted: Schedules and procedures for
inspecting safety and monitoring and emergency equipment. The applicant shall
develop and follow a written inspection procedure acceptable to the Director for
inspecting the facility for events or practices which could lead to unauthorized
discharges of� hazardous materials. An inspection check sheet shall be
developed to be used in conjunction with routine inspections. The check sheet
shall provide for the date, time, and location of inspection; note problems and
dates and times of corrective actions taken; and include the name of the
inspector and the countersignature of the designated safety manager for the
facility.
(C) Five to Ten Year TOTZ Standards.
(1) The storage, handling, treatment, use, production or otherwise keeping on
premises of more than 20 gallons of hazardous or other_materials that pose a risk
to groundwater in aggregate quantities not containing DNAPLs is allowed only
upon compliance with containment and safety standards specified by the most
recent Fire Code adopted by the City.
(2) All hazardous or other materials that pose a risk to groundwater shall be stored
in areas with approved secondary containment in place (Springfield Fire Code
5002.1 and 5004.2.2).
(3) All new uses of DNAPLs are prohibited.
(4) Any change in type of use or an increase in the maximum daily inventory
quantity of any DNAPL is considered a new use and is prohibited.
(5) The following requirements for inspection and record keeping procedures for
monthly in-house inspection and maintenance of containment and emergency
equipment for all amounts of hazardous or other materials that pose a risk to
groundwater shall be met unless exempted: Schedules and procedures for
inspecting safety and monitoring and emergency equipment. The applicant shall
develop and follow a written inspection procedure acceptable to the Director for
inspecting the facility for events or practices which could lead to unauthorized
discharges of� hazardous materials. An inspection check sheet shall be
developed to be used in conjunction with routine inspections. The check sheet
shall provide for the date, time, and location of inspection; note problems and
dates and times of corrective actions taken; and include the name of the
inspector and the countersignature of the designated safety manager for the
facility.
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Ordinance No. 6464
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(D) Ten to Twenty Year TOTZ Standards.The storage, handling, treatment, use,
production or keeping on premises of more than 20 gallons of hazardous or other
materials that pose a risk to groundwater in aggregate quantities is allowed only upon
compliance with containment and safety standards specified by the most recent Fire
Code adopted by the City. (6443; 6238)
3.3.240 Conditions.
The Director may attach conditions of approval that will minimize negative impacts of regulated
substances on groundwater and ensure that the facility or the proposed development can fully
meet the standards specified in SDC 3.3.235. These conditions may include, but are not limited
to: on-site monitoring wells, Wellhead Protection Area signs, special storm-water facilities,.or
other conditions to address specific risks associated with the proposed development.
Commentary. The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to
encourage green street design (with the use of swa/es, planters, rain gardens and other
features to reduce runoff and pollutants) and to comply with the MS4 Permit to encourage the
use of Low Impact Development.
4.2.100 Infrastructure Standards —Transportation
4.2.105 Public Streets.
(C) Minimum street curb-to-curb widths and minimum street right-of-way widths are as
specified in Table 4.2.1, unless otherwise indicated in the Springfield Transportation
System Plan, an applicable Refinement Plan, Plan District, Master Plan, Conceptual
Development Plan, or the adopted bicycle and pedestrian plan; where necessary to
achieve right-of-way and street alignment; or as needed to meet site-specific
engineering standards, including, but not limited to, requirements for multi-way
boulevard and/or modern roundabout designs. Streets may include Low Impact
Development approaches, such as stormwater planters, swales, rain gardens and tree
planting to reduce stormwater runoff from impervious surfaces. Example street layouts
meeting minimum street standards are provided in Figures 4.2.13 through 4.2.V for
illustrative purposes only. These Figures are intended to demonstrate potential street
configurations that meet the requirements.
Commentary. The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to allow
stormwater quality facilities in sidewalks. Low Impact Development approaches may be placed
in sidewalk planter strips provided they meet the provisions in the Engineering Manual (EDSPM)
and SDC 4.3.110.
4.2.135 Sidewalks.
(D) Planter strips are required as part of sidewalk construction. Planter strips must
be at least 4'/2 feet wide (as measured from the back of curb to the edge of the
sidewalk) and at least 4'/2 feet long. Planter strips must have approved
landscaping consisting of street trees—aground cover—
and al&G-ma
=y
include Low Impact Development approaches allowed-peFin accordance with the
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applicable provision in the Engineering Design Standards and Procedures
Manual and SDC 4.3.110. Tree wells set in concrete or sidewalk areas must be a
minimum of 4 feet by 4 feet. Concrete, asphalt, or other impermeable pavement
are not allowed to substitute for landscaping within planter strips. Planter strips
less than 4'/2 feet wide may be permitted when necessary for connectivity, safety,
or to comply with street design requirements, subject to approval by the Director.
(E) Maintenance of sidewalks is the continuing obligation of the abutting property
owner.
4.3.110 Stormwater Management.
Commentary: Amendments to 4.3.110(A) adds a definitions section, defines terms as required
or recommended by the permit, and clarifies that definitions in this Section apply to the
Stormwater Management section.
(A) Definitions. For the purposes of this section only, the following definitions apply.
Additional definitions are provided in SDC 6.1.105 or SDC 6.1.110. Unless specifically
defined below or in SDC 6.1.110, words or phrases used in this section shall be
interpreted so as to give them the meaning they have in common usage.
1W Maximum Extent Practicable (MEP) is the technology-based discharge standard
for municipal separate storm sewer systems to reduce pollutants in stormwater
discharges that was established by Section 402(p)(3)(B)(iii) of the Clean Water
Act [33 U.S.0 §1342(p)(3)(B)(iii)1.
2Q Minimize means to reduce and/or eliminate to the extent achievable using control
measures (including BMPs) that are technologically available, economically
practicable, and achievable in light of best industry or municipal practices.
Commentary: Amendments to 4.3.110(B) adds an Applicability section, complies with the
language from the permit and existing code by requiring structural storm water controls for 5,000
square feet or more of impervious surface, and requires a Stormwater Study for development
that generates runoff from more than 1 acre of land or peak flows in excess of 0.5 cubic feet per
second. Since the August 1, 2023 hearing, Lane County provided feedback to remove the
underlined clause in SDC 4.3.1 10(B)(1): "Development that creates or replaces 5,000 square
feet or more of impervious surface area and discharges to the storm system...". The phrase
"discharges to the storm system"is intended to include sites that drain to the City's MS4 permit
area. However, the City's MS4 permit area includes the entire Springfield UGB and so this
phrase is unnecessary. It also creates confusion related to sites that choose to meet the site
performance standard by infiltrating the first 1.4"of rainfall in 24 hours; these sites will still
discharge to the storm system during very large storm events and are still subject to SDC
4.3.110. Therefore, to avoid confusion and remove unnecessary language, City and County
staff recommend removing this clause.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 11 of 35
Ordinance No. 6464
Exhibit A Page 12 of 133
(I) Applicability. The following development activities require the use of a site-specific
stormwater management approach that incorporates one or more structural stormwater
controls:
(1) Development that creates or replaces 5,000 square feet or more of impervious
surface area and d0scherGraes to the storm system•
(2) Development that disturbs one or more acres of land within the development
area; and
(3) Development that generates peak flows in excess of 0.5 cubic feet per second
within the development area.
Commentary: Amendments to 4.3.110(C):
• Define the two types of performance standards for structural stormwater control facilities
and comply with the MS4 Permit requirements.
• Stipulate that the stormwater system is separate from the sanitary sewer and that
discharge of stormwater to the sanitary sewer system is prohibited.
• Require that all structural stormwater controls must be designed, operated, and
maintained to comply with the Appendices in the Springfield Development Code or
Engineering Manual.
• Move SDC 4.3.110(6) Identification of Water Quality Limited Watercourses and SDC
4.3.110(7) Protection of Riparian Area Functions to SDC 4.3.115 Water Quality
Protection.
• Address permeable pavements, injection wells, on site source controls for high risk land
uses (which previously resided in Chapter 3 of the EDSPM and is now in Appendix H of
the SDC), and roof mounted equipment.
• SDC 4.3.110(C)(1) was amended to reference the correction SDC section for the
Stormwater Study reference (SDC 4.3.110(E) instead of SDC 4.3.1 10(D)).
(A C) Stormwater Management Improvements Structural Controls —General Standards.
(1) Engineered Design Requirement. The Stormwater Study required under
section 4.3.110k94(El and All stormwater FnaRagemeNt system rdesigR ORGI 1 IIN
supporting documentation for the design of the proposed stormwater structural
controls must be prepared and stamped by an Oregon licensed engineer.
/')\ A steFrn ateF management system must be iRstalled to servo eaGh Rew
�/ de"elepment V.githiN the city limits
2Q Technical Standards. The Stormwater Study required under section 4.3.110(Dl
must demonstrate compliance with one of the following performance standards:
fa Site Performance Standard: The first one and four tenths inches
rainfall from each storm event must be routed to one or more structural
stormwater controls with sufficient capacity to fully infiltrate,
evapotranspirate, and/or be reused on site without stormwater runoff
discharging from the site: or
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 12 of 35
Ordinance No. 6464
Exhibit A Page 13 of 133
Ub Treatment Standard: All rainfall not retained onsite, up to the first one and
four tenths inches (LAa of rainfall from each storm event, must be treated
in compliance with the standards and design criteria in SDC 4.3.110(Dl.
(3) The stormwater FnaRagerneRt system must be desir Red and G()RStri inter! ire
(341 Discharge to Sanitary Sewer Prohibited. The stormwater management system
must be separated from and not discharge to, any public or private sanitary
sewer system.
4 Facility Design Standards. The structural stormwater controls must be
designed, operated, and maintained consistent with the requirements in the
facility-specific design requirements provided in Appendix D Typical Stormwater
Facility Details. Unless an alternative is approved under the Treatment Standard_
stormwater controls that include vegetative treatment must incorporate only
those plant species listed in Appendix F.
(5) Construction Standards. on.Y d_eXYelnement that creates er renlanes ti non
s g 6i arezeet e r mere of i m ee Y Yviva.�i rf Tea a d -,argv s-t9 the stvr�mrr
system mi ist install storm �nYater rentrels that minimi-7e the amni int and! rate of
31_4�;RceVater r1 ate the ^ity ster,,,�ater system.The ster,Tsysten4All
stormwater structural controls must be constructed consistent with the
Engineering Design Standards and Procedures Manual ser?tiensT03.1, 4.03.2,
and 4�-Chapter 4.
identifiGation of Waaterc� Quality Limited Wa-terGeurses. Thevnrr"eEteror Must
maintain a Water Q 4ity Limited \n/aterrni uses (\AQ1 \n/) Hoar, en file in the
VVQ \n/Hoar, mi ist he anereyed_ by the Git y (`ni innil as an amendment to this
ode Those nYaterrni uses and their direct trihi itaries inrli idled! en the\n/Q \n/
Map haven heen fei ind to VYarrant eretertiVe measi Tres in si ineert of the Gity's
reseense to State and_ Federal rent nations regarding si irfane anal si ihsi irfare
discharging stermwater management systems by satisfYing the fellewing
�d-
(1� Water Q 4ity Limited \n/aterrei uses (\n/(ll VV) \n/aters of the State that
meet 'I nr more of the fnlIGWing stand_ard_s•
�T \n/aternni arse reaches 'Yong within the Git y and_ its i irbaniZing
`•' area that are innli idled_ by the State of nregen flenartment of
Cniiirnnmental Q 4ity (GI)EQ) OR its most rerent'Y adopted
"303(d)" Lost of Impaired and_ Threatened_ \n/aterhndies
ITT \n/aternni arse reaches 'Yong within the Gity and_ its i irbaniZing
`••' area with significant water gi iality impairment identified_ by water
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 13 of 35
Ordinance No. 6464
Exhibit A Page 14 of 133
(b) 4 d-irent trihi itary to a VVQI sfi\n/that saties rJ r the fnlln,niing Standar
��""''� RY waternni irco +h.+fln,nic diFeGtly iRte a FAQ VnV I--Ieweyor,
evc��te d' r�ve�t�t flev.g iRto the VVQLVV as a-piped-
where-the pope systern e�gtepds mprithap 290feet 6iFstrean; Gf
Oho gennegtien Point are net gensid-ered- as fIGGYAng into a \AQI \n/
i ind-er this stand-ard-
Lam! An,i watergei arse that is dive-rsien from a IAQ Wand- that
`••, d-isgharges into either a VVQ VV er ether d-iregt tribe itar,i to a
IAQ VV and- ,nihere the ,ester gi iality of the diverted- flev.g at the
d-isgharge eeint has been degraded ,eiheR gerrmeared- with the
,neater gi iality at the d-iVersien Point
6 Permeable Pavements. Permeable pavements may be used to reduce the area
of impervious surfaces and shall be constructed consistent with the Engineering
Design Standards and Procedures Manual. Permeable pavements cannot be
used for treatment of stormwater from other impervious areas.
(74 Prue Gtien of Riparian Area FunGtionc /A d-eyeleper is ..,.,Fed to emplev cite
design land-sganing and- drainage management nrartires to nretert nreseFye
and! restore the riparian area fi, m' iens of the reaches of these
,e m n (l
,niaternni uses
she e the\n/ l ne W ar, that are remained- within er ahi it the let/panel i rope
,eihirh the nrenesed- d-eVelenment is legated- Cer the ni ernes es of this ged-e
rir�arian arm fi innnn� idle hi it are not limited! tn-
�h'arrarr-ar Tune rr rr acre-are��vrnrrrrcea cv.
(aa) MaiRtaiRiRg-ter;perat6ir
(h) inning At_Ql st ili ,
(n) PFGVmd-ing flood- storage;
Tv� vv�nrr9��wcr u�c+
(d) PFG md-ing grei Ind-.A.aterTeGhaarge;
(e) ReR g-sed+reentS;
M D uEFRg-C$-tamirarts�for examp,le• e3C?sS Rr cr trFelrts• eirls urd gr ease•
metals; and- feral nnlifnrm•
o
(g) Medera-tmg stermvvater flews; aRa
(h) PFe,ii� TSh and- Vyild-life hahit;;t•
J7 Injection Wells. Except where prohibited by this code, underground injection
wells are allowed only wjth approval from the Department of Environmental
ualit .
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 14 of 35
Ordinance No. 6464
Exhibit A Page 15 of 133
8 On Site Source Controls for High Risk Land Uses. Where an application
proposes one of the following high-risk uses, the application must comply with
additional standards as provided in Appendix H On Site Source Controls:
CB Site Uses and Characteristics That Trigger Source Controls
CQ Fuel Dispensing Facilities.
LD Abovearound Storage of Liquid Materials.
LE Solid Waste Storage Areas. Containers. and Trash Compactors.
CF Outdoor Storage of Bulk Materials.
G) Material Transfer Areas.
LH Equipment and/or Vehicle Washing Facilities.
I Covered Vehicle Parking Structures.
9 Roof-mounted Equipment. All rooftop mounted equipment shall be provided
with secondary containment or a weather resistant enclosure to ensure that. in
the event of a leak or spill, any fluids cannot migrate into a public or private
stormwater system or to any underground injection control facilities.
Commentary: Amendments to 4.3.110(D):
• Stipulate that a Type 2 application process is required when the Alternative Treatment
Standard is proposed.
• Define the terms of technical infeasibility or site constraints for the Alternative Treatment
Standard.
• Stipulate that all development must retain rainfall onsite to the maximum extent
practicable and any rainfall not retained onsite, must treat up to the first one and four
tenths inches (1.4') to achieve no less than 80% removal of total suspended solids. All
stormwater not retained onsite must be discharged to the public stormwater system.
• Structural stormwater controls used to meet the Treatment Standard must incorporate
Low Impact Development.
(D) Treatment Standard —Criteria. The following provisions apply to review of an
application that proposes to meet the Treatment Standard under SDC 4.3.110(C)(2)(a1
above.
(1) Type 2 Review. An application that proposes to comply with the Alternative
Treatment Standard must be reviewed through a Type 2 application process in
accordance with SDC 5.1.400, except when proposed for a development that is
subject to Type 3 review, in which case it may be approved through a Type 3
review.
(2) Applicability. An application that proposes to comply with the Alternative
Treatment Standard must demonstrate that the Site Performance Standard
cannot be retained and infiltrated on-site due to technical infeasibility or site
constraints.
(a) Site constraints that may be used to demonstrate technical infeasibility
under this subsection include but are not limited to shallow bedrock. high
groundwater, protection of groundwater from contamination, soil instabilitv
as documented by geotechnical analysis required elsewhere by this
Code, land use that is inconsistent with capture and infiltration of
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 15 of 35
Ordinance No. 6464
Exhibit A Page 16 of 133
stormwater, the known presence of soil contamination, or constraints
arising under the provisions of the Drinking Water Protection Overlay
District in SDC 3.3.200.
(b) An applicant is not required to demonstrate that it is technically infeasible
to evapotranspi rate and/or reuse rainfall onsite to meet the Site
Performance Standard.
(3) Design Standards.
Ua The development must retain rainfall onsite to the maximum extent
practicable.
Ub All rainfall not retained onsite, up to the first one and four tenths inches
1.4") of rainfall from each storm event, must be treated to achieve:
ja Reduction in the discharge of mercury, bacteria, and heavy metals
to the maximum extent practicable; and
ii No less than 80% removal of total suspended solids (TSS) for
typical influent concentrations ranging from 100-200 ma TSS per
liter; or
iii For atypical influent concentrations less than 100 ma TSS/L or
greater than 200 ma TSS/L. an alternative treatment standard
may be required to target an equivalent water quality_ benefit as
onsite retention.
Up Detention ponds cannot be approved as a stand-alone treatment method
and must be combined with Low Impact Development.
Jd All stormwater not retained on site must be discharged to the public
stormwater system. Conveyances to the public stormwater systems must
be designed to accommodate, at minimum, the peak runoff for the 25-
ear rainfall event for the entire tributary area. Exception: If the discharge
of the runoff for the 25-year rainfall event is determined likely to exceed
capacity of the public stormwater system or if said discharge would result
in floodina, the conveyance must be designed to accommodate the peak
runoff for the 100-year rainfall event.
(4) Low Impact Development (LID) Required. Structural stormwater controls used
to meet the Treatment Standard must incorporate Low Impact Development "LID
as provided in Appendix D to the maximum extent practicable.
(5) Vegetation Standards.
Ua Trees that are required to be planted on-site under the provisions of this
code must be planted to provide shade to the stormwater facility to the
maximum extent practicable.
Lb Construction and planting must occur under conditions (such as
temperature, moisture level, and handling) that prevent soil compaction
and erosion. Any imported soil must be a sandy loam mixed with compost
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 16 of 35
Ordinance No. 6464
Exhibit A Page 17 of 133
or a sand/soil/compost blend. Soil must be at least one-third compost by
volume, be free-draining, and support plant growth. The compost must be
derived from plant material; animal waste is not permitted.
Commentary. SDC 4.3.110(E) clarifies that a Stormwater Study is required for any
development that installs a structural stormwater control as defined in SDC 4.3.110(8) above.
The Study must detail how the proposed stormwater control targets natural surface or
predevelopment hydrologic function and provide a hydrological study map that meets the
standards in 4.3.110(E)(2)(b).
(8 E) Stormwater Study Standards.
(1) An applicant must complete a Stormwater Study, as ^61tliRed be'G , m616t ho
ri inn#from mnro thin GRe aGFe of 1and nr generate peak flev.gs in ovross of O F
rfs 4ppliGatinns fnr deVelnPmont th At nro R4oc 5,000 sr,i i;ro foot of no n,
a GapaG ty of 0.5 Efs-oF gTeater a GG)Mpletta Ster„ water StHdy
for any development requiring the installation of structural stormwater controls as
specified in SDC 4.3.110(Bl.
rese61FGe area er wellhead prQtest+e ZZsn "st iAE 'd_eQ ip the-s,H�wed
Sterm,Trvvater StHdy a reVTe.4 �apd_TepGFt OR the impaEt to these.
(2) A Stormwater Study must include the following:
(a) A written narrative describing the proposed stormwater management
syste�n-a p� in detail, describing how the approach targets natural
surface or predevelopment hydrologic function through the installation
and long-term operation and maintenance of the proposed structural
stormwater controls. iRGl6l liR9 GGRAP-^4i„RIS to the P 1bliG stnrm1e9;;tor
MaRage!MeRt System, r�a de6GFitinn addFossinrr water 9 i iality meas Tres
(Rost MaRa eMeRt DraGtiGeS) PrnPE)69d 0 as well as an" ReGeSSaFy
Ear ;�easuTes t#a he�eg�ed fe Pmerat�.e. a
deteRtie„-pGRd) aG Bete edbyth9Ster,,,PateF9 .
(b) A hydrological study map, that contains all of the following for 4the
development site and adjacent areas that contribute in excess of 0.1 cfs
from offsite flows;WL911 e( and an area beyond the development site
of not less than 100 feet:;
(4=U Streets adjacent to or hydrologically connected to the
development area, and street names;
(4i-ii) Flow arrows in streets and ditches;
(W iii) Contours or spot elevations for verification of direction of overland
flow and pipe cover; Contour intervals on the study map must be
as follows:
Slope Contour Interval
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 17 of 35
Ordinance No. 6464
Exhibit A Page 18 of 133
(%) (Feet)
------- --------
0 - 10 2
11 - 25 5
>25 10
(v iv) Drainage areas of all sub-basins (in acres);
(v4 v_) Collection points (nodes) at downstream limits of all sub-basins;
(v4 vi) A profile of the stormwater management system showing invert
elevations, maintenance access hole top and bottom elevations,
existing utilities, and existing and finished ground line elevations;
(vW vii) Existing and proposed stormwater pipes and r-" Tsurface
waters with sizes and/or cross-sections included;
(+*viii) Future pipes in the system, complete with proposed sizes, slopes,
pipe cover, and flow line elevations at maintenance access holes;
(* ix) North arrow, scale, Engineer's name and contact information, and
date;
(�c+x) Environmentally sensitive areas (e.g. gullies, ravines, swales,
wetlands, steep slopes, springs, creeks, etc.) and direction of the
flow of natural drainage features;
(*+i-xi) 100-year flood plain with flood elevations and 100-year flood way
and,
*+F xii The location of all locally significant natural resource areas. Water
Quality Limited Watercourses, or wellhead protection zones.
(c) A report describing development impacts to any floodplain or floodway.
(s d) Hydrologic calculations to establish runoff volumes and peak flows-cas
(d e) Hydraulic calculations to establish pipe size, flow velocity, and hydraulic
grade line.
Commentary. SDC 4.3.110(F) amends the stormwater study types to be either a Small Site
Study or a Full Site Study(a Mid-Level Site Study was removed from the code). A Small Site
Stormwater Study is permitted when a site is less than 1 acre, meets the site performance
standard in 4.3.110(B)(2)(A), and does not contain or is abutting a floodplain/f/oodway, locally
significant natural resource area, wetland, or riparian area; Water Quality Limited Watercourse,
or well-head protection zone. For sites that cannot meet these standards, a Full Site Study is
required.
(6 F) Stormwater Study Types
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 18 of 35
Ordinance No. 6464
Exhibit A Page 19 of 133
(1) A Small Site Stormwater Study is required when all the following criteria are met:
(a) The proposed development is on a site that is less than €gone acres in
size for a residential development nr is a Gnmmernial indl Istri;l' nr
use
mixed se deyeleprvmeRt that is OR a site that is GRe aGre gr loss ir, -"--
and the onsite stormwater basin structural controls do not treat anv single
drainage basin larger than 15,000 square feet impervious area.
(b) The development meets the Site Performance Standard as provided in
4.3.110(Q(2)(A). s+I Id„ area drains in+n an axis+inn pI Ih1iG +nrm,e„ter
management system With ;,iail;hle Gapanit,i as determined by testing
performed by an nregnn IiGensed Cngineer M Gnnfnrm;nre ,niith the
E�g2+l�Qt9rm�rrv"Patei n n a n l I a 1 for the pea L fl non �h a��e���t��-atvi�mrrL Q A
fregl IenG,i reel lire`•! I Inner R-DG it Q 110(D)
(c) The study area does not contain or is not abutting to any of the followina:
a floodplain or floodwavI stream we+land locally sianificant natural
resource area, wetland, or riparian area: or Water Quality Limited
Watercourse. nr,e9e11 hear) pro+eG+inn Znne
resnl Irges that are nn ;n ;dnp+ed in,ien+nr,i nr man nr resnl Imes +hat are
adep+ed as part of the\AQVVL man are applirahle I Inner this standard
(2) A Mod Level Site SteFrnwateF Study is FequiFed wheR the GFiteFia fGF a Small Sitem
ate� St6ldy G;nnnthe met ;;Ad hap A Imo- Of thtQ WIGWORg nteria-are met-
(a) The dreV PR;eRtarea inGII Iding aRy hydra Ilinally GnnneGted area G_.Arthe
same pmpert,i is less than, 25 aGres ir, sire
(p T� Gde�`' o
) The pR;eR area,ORG IdIng aRy ydrivaiTGally GRReGted area G_.Arkhlt:.
same property, drains to ;n estahlished pI Ih1iG system Within the Git,4
III
(G�)The deV pn-,eRt area, inGll lding aRy hydrraa6IITGaIhi GORReGted aareay.A thea
same arty,y, dGerG RG-t GX 66 RettaddjaEeAt-t8 a floodplain, stream,
wetland, +I na Iral resnl Irge area, well oll head pretentinn iznne
(32) A Full Site Stormwater Study is required when the criteria for a Small Site aid
nnid_i e14e1 Site Stormwater Study cannot be met_. and ,^,here ;n„ of the fnllGWing
Gnndi+inns are met•
(aa) The deV pmeRt area, inG11 Nogg aRy hyddral IIiGally GnnneGt9d area G_.A the
same property, is greater than 25- ;Gres in si-e
(b pm is eq 're R Of eutfall acid/gr the stnrmwat
e�F e�-lrrt t-r".luir�Ereatf6 �r-cn-rcn-vr rr....cvrrrrvracer
from the At-BW development ,n9011 evreed the evicting stormwater
e developmeRt area, Tf dINg aprtyt rhry'dFaWliGally GGR reEted-caFea GR the
same erty,,-GGRta�R$ GF is adjaeepttG_ a fleedplaiR, stream, wetla`•'drrd,-^of
n;+I Ir;l resnl Irr•e area
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 19 of 35
Ordinance No. 6464
Exhibit A Page 20 of 133
(d) An" d prn flow f
e�F en+ t�era eFa-tes-a-pea,k�'n Te�(�S�O,--0.5
GfST
MG_rJifioc a eXis+ino s+ormRn,a;+ter manageMeRt sys+tern Vn,i+h a G.aoa Got" of
0.5 nf6 ter greatter, ter is a FedeyeleprneRt ter Rew deyeleprne t that GFeates
5,090 soi iarte ftete+ er mere of ReW iFnperyioi is area
Commentary. SDC 4.3.110(G) amends the stormwater study hydrologic calculation standards
for a small site stormwater study or a full site study. For a small site study, the calculations must
demonstrate compliance with the Site Performance Standard (calculations must use a value of
1.4"over 24 hours) or the Treatment Standard (calculations must use an intensity of at least
0.13 in/hr for off line facilities and 0.22 in/hr for online facilities) and be supported by the
methods and calculators in Chapter 4 of the Engineering Manual. For a full site study, the
calculations must be supported by calculations using the unit hydrograph method and the storm
event frequencies in Table 4.3.1.
(D-Q) Stormwater Study Hydrologic Calculation Standards. The stormwater study required
under SDC 4.3.110(G F) must be supported by hydrologic calculations that conform to
the following standards:
(1) A small site stormwater study must be supported by hvrdroloaic calculations
using the rational method or a unit hydrograph method (as required for a full site
stormwater study in (2) below. The rational peak flow method, Q=CiA, where `Q'
is the peak flow, `C' is a runoff coefficient, `i' is the rainfall intensity, and `A' is the
catchment area. Rainfall intensity and design storm requirements must be used
as provided in 4.3-110(C12, as fps
(te�a) .Abed the-r,,nzrnvff veetiTcieR� is 0.5- er greater, the eaL flow fvr
imrter"itei is si irfaGes must be GaIG elated separately fFern the peFyie is
��rf c nrl romotered to the eak flo ��_� Te— Fi-Ie
higher of the two peak flev.g rates mi is+ hte 11sead ; s the peak floe, r;;+te for
the of irPnSL-Q Of thi-9 vrmi-rrvPatci Stlld_�Lr
La To demonstrate compliance with the Site Performance Standard,
calculations must use a value of 1.4" over 24 hours using the type 1a
SCS storm inten�+siit�y/cu e
(b) Per oI irpeseaT 17f GTtatG iniRg Whetht-BF cutG_.F nV.4ateF y�vtL�I�c�ra$
terte mte+ i isinrr•�the ratiGRal methurl a rainfall in+tense+v `i' of 9.25 inch Per
hoe it mi is+ 1949 11549d +o GaIG 4ate peak flAw
(b) To demonstrate compliance with the Treatment Standard, calculations
must use an intensity of at least 0.1 3inch/hour for off line facilities and
0.22inch/hour for online facilities, up to the maximum extent practicable.
(G) F=9Tthe-purposes of deteFrniRiRg-steFrnwateF Gaae+ty- siRg-the Fat+e al
peak flew method the rainfall in+tensity `i° mi is+ hte nalni ila+ter! i icing the
Intensity D Faber F=Feq itenn" ni lFyes #ern the West SpFiRgfielyd DFaiRage
54tes+ter DlaR (1983) (ayailtehlte in Ghaptter it of the -Pginteterinry / esigq
St Eed, es Manual). The steFrnn eveRt #equeRdies OR SDG
Table 4.3.1 m,is+ hte 1 lsterl:
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 20 of 35
Ordinance No. 6464
Exhibit A Page 21 of 133
(c) A small site stormwater study that is supported by the methods and
calculators provided in section 4.03.1 of the Engineering Design
Standards and Procedures Manual will be approved without reguirina
additional documentation or support for calculations.
T2hln A 4 1 Storm Event Crequennies
DeaL F4Gw Ronne Storm Event Crone ienn!i
r q ' year storm event
F nfs to <20 ofs F_year storm a lent
20 ofs to -4(1 ofc 'IQyear storm a lent /'I
50 year storm eient
(1) The 25 year storm oven# mov he required when ropority issi ies
are irlentifierl during o Type 2 or Type 3 review process
(2) A M,d—level Site 2—termi.vater Study and full site stormwater study must be
supported by calculations using the unit hydrograph method.
(a) The Natural Resources Conservation Service (NRCS) SCS Type 1A
distribution must be used (provided in the Engineering Design Standards
and Procedures Manual for reference). The Storm Event Frequencies in
Table 4.3.1 must be used.
Table 4.3.1 Storm Event Frequencies
Recurrence Interval 2 5 10 25 100
Years
Flood Control 3.12 3.6 4.46 5.18 6.48
Destination:
24-Hour De the
Inches
Water Quality Storm — Pollution reduction: 24-Hour Depths, 1.4 Inches
(b) For the purposes of determining whether stormwater quality standards fer
mir-I_le„el ;;Ad fi,n site a rainfall intensity of 8-831.4 inches per 24-hour
period must be used.
Uc A full site stormwater study must include floodplain analysis if the
development will affect the floodplain. The 100-year Reed storm event
frequency must be used for development within the floodplain.
Commentary. The Operations and Maintenance Requirements in the Engineering Manual were
added to the code to ensure that all structural controls installed in compliance with the MS4
permit are operated and maintained to meet site performance or alternative treatment
standards.
( ) Operations and Maintenance Requirements.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 21 of 35
Ordinance No. 6464
Exhibit A Page 22 of 133
(1) All structural stormwater controls must be operated and maintained to continue to
meet the Site Performance Standard or alternative Treatment Standard as
applicable.
(2) The owner of property subject to any application that proposes structural
stormwater controls that will be privately-owned and operated must enter into an
Operations and Maintenance Agreement with the City. The Agreement must
specify at least the following:
(a) A plan to maintain and operate the structural stormwater controls to
continue to meet the Site Performance Standard or alternative Treatment
Standard, which may include but is not limited to operations and
maintenance requirements in Appendix E.
(b) For structural stormwater controls that include vegetation, requirements to
maintain and/or replace vegetation to ensure at least 90% vegetative
coverage; and;
(c) For structural stormwater controls that include soils in the treatment
process, requirements to maintain soil permeability and plant health; and
(d) Reporting requirements to document compliance with onaoina operations
and maintenance requirements.
(3 For any property that is subject to an Operations and Maintenance Agreement. a
Notice of Operations and Maintenance Agreement (NOMA) must be recorded
with Lane County Deeds and Records. The NOMA must be in a form approved
by the City, be sign by the property owner and properly_ notarized, and include a
legal description of the subject property.
Commentary: SDC 4.3.115 was amended to move SDC 4.3.110(6) Identification of Water
Quality Limited Watercourses and SDC 4.3.110(7) Protection of Riparian Area Functions to this
section for clarity and consistency. Clarification was provided to require site design,
landscaping, and drainage management practices to protect, preserve, and restore riparian area
functions.
4.3.115 Water Quality Protection
(A) Applicability. These regulations apply water quality protection to only those sites that
require Minimum Development Standards Review as specified in SDC 5.15.100, Site
Plan Review approval as specified in SDC 5.17.100, and Land Divisions (Partition
Tentative Plan and Subdivision Tentative Plan) approval as specified in SDC 5.12.100,
or that disturb more than one acre of land through a Type 1 review. The following
standards do not apply to single unit dwellings duplexes, or middle housing in the R-1
District that disturb less than one acre of land, unless as specified in SDC 4.3.115
(,413)(1). Existing buildings that are within the riparian areas specified in SDC
4.3.115(AB)(1) and (2) are not considered non-conforming. SDC 4.3-115(AB)(2)(a) and
(b) provide additional protection from a non-conforming status.
L13 Identification of Water Quality Limited Watercourses. The Director must maintain a
Water Quality Limited Watercourses (WQLW) Map on file in the Development Services
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 22 of 35
Ordinance No. 6464
Exhibit A Page 23 of 133
Department, which designates certain watercourses and their direct tributaries within the
City and its urbanizing area. Any revision to the WQLW Map must be approved bv_ the
City Council as an amendment to this Code. Those watercourses and their direct
tributaries included on the WQLW Map are Waters of the State that have been found to
warrant protective measures in support of the City's response to State and federal
regulations regarding surface and subsurface discharging stormwater management
systems, by satisfying one or more of the following standards:
(1) Watercourse reaches. lying within the City and its urbanizing area, that are
included by the State of Oregon Department of Environmental Quality (ODEQ)
on its most recently_ adopted "303(d)" List of Impaired and Threatened
Waterbodies.
(2) Watercourse reaches. lying within the City and its urbanizing area, with
sianificant water quality impairment identified by water quality monitoring and
sampling done in accordance with approved quality assurance/quality control
QA/QQ protocols.
(3) A direct tributary to a WQLW that satisfies the following standards:
(a) Any watercourse that flows directly into a WQLW. However, watercourses
that flow into the WQLW as a piped connection, where the pipe system
extends more than 200 feet upstream of the connection point are not
considered as flowing into a WQLW under this standard.
(b) Any watercourse that is a diversion from a WQLW and that discharges
into either a WQLW or other direct tributary to a WQLW and where the
water quality of the diverted flow at the discharge point has been
degraded when compared with the water quality at the diversion point.
(C) Protection of Riparian Area Functions. A developer is required to employ site design.
landscaping, and drainage management practices to protect, preserve. and restore the
riparian area functions of the reaches of those watercourses shown on the WQLW Map
that are contained within or abut the lot/parcel upon which the proposed development is
located.
(1) For the purposes of this Code, riparian area functions include, but are not limited
to:
(a) Maintaining temperature,
(b) Maintaining channel stability;
(c) Providing flood storage;
(d) Providing groundwater recharge.
(e) Removing sediments;
(ff) Reducing contaminants, for example: excess nutrients; oils and grease:
metals; and fecal coliform;
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 23 of 35
Ordinance No. 6464
Exhibit A Page 24 of 133
(g) Moderating stormwater flows: and
(h) Providing fish and wildlife habitat.
(2) The following standards apply to the protection of water quality and protection of
riparian area functions specified above:
(a) Avoid development or redevelopment in the following circumstances:
(i) Unsuitable areas, including, but not limited to, unstable slopes.
wetlands and riparian areas;
(ii) Stream Crossings. Where crossings have to be provided, the
impacts on water quality must be minimized to the maximum
extent practical; and
(iii) Hardening or armoring of stream banks and shorelines.
(b) Prevent:
(i) Stormwater discharge impacts to water quality and quantity; and
(ii) Erosion and sediment run-off during and after construction.
(c) Protect:
(i) Riparian areas, buffers, and functions around all watercourses;
and
(ii) Wetlands, wetland buffers and wetland functions.
(d) Preserve the hydrologic capacity of any watercourses.
(e) Utilize Native Vegetation in Riparian Areas. The required riparian area
landscaping must be installed as part of the building permit process and
may be bonded as specified in SDC 5.17.150.
(f) Restore and enhance riparian areas that are degraded in riparian
function.
(3) In applying SDC 4.3.115(C)(2) above, riparian area protection, preservation,
restoration, and enhancement measures must be applied as follows:
(a) For new development and redevelopment, existing riparian area functions
must be protected and preserved. Degraded functions must be restored
or enhanced through the full riparian area width, as specified in SDC
4.3.115(A)(1) and (2), and extending through the full frontage of the
lot/parcel along the watercourse on the Water Quality Limited
Watercourse (WQLW) Map.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 24 of 35
Ordinance No. 6464
Exhibit A Page 25 of 133
(b) For additions and expansions on any portion of a lot/parcel, existing
riparian area functions must be protected and preserved through the full
riparian area width specified in SDC 4.3.115(A)(1) and (2), and extending
through the full frontage of the lot/parcel along the watercourse on the
WQLW Map.
(c) For additions and expansions within 100 feet of a watercourse on the
WQLW Map on a lot/parcel that has degraded riparian functions. the area
for restoration or enhancement must be based upon the ratio of the
impervious area of the addition or expansion to the existing building or
impervious area on the lot/parcel. The restoration or enhancement must
start at the top of bank of the watercourse and work landward.
(A D) Riparian Area Boundaries. When addressing criterion (E) as specified in SDC
5.12.125, for Land Divisions, and SDC 5.17.125 for Site Plan Review to protect riparian
areas along watercourses shown on the Water Quality Limited Watercourses (WQLW)
Map, the following riparian area boundaries must be utilized:
(1) Along all watercourses shown on the WQLW Map with average annual stream
flow of 1,000 cubic feet per second (CFS) or greater, the riparian area boundary
is 75 feet landward from the top of the bank. Existing native vegetative ground
cover and trees must be preserved, conserved, and maintained between the
ordinary low water line and the top of bank and 75 feet landward from the top of
bank.
Within the Willamette Greenway, any change or intensification of use to a single
unit dwelling or Middle Housing requires Site Plan Review as specified in SDC
3.3.315. through the Site Plan Review process the Director may reduce the size
of the required riparian area if there is a finding that the proposed development is
in compliance with SDC 3.3.300, the Willamette Greenway Overlay District, SDC
3.2.280 and other applicable provisions of this Code.
(2) Along all watercourses shown on the WQLW Map with average annual stream
flow less than 1,000 CFS the riparian area boundary is 50 feet landward from the
top of the bank. Existing native vegetative ground cover and trees must be
preserved, conserved, and maintained both between the ordinary low water line
and the top of bank and 50 feet landward from the top of bank.
(a) For all watercourses subject to Subsection 4.3.115(A)(2), other than the
Mill Race or Cedar Creek, the 50-foot riparian area standard may be
reduced to 35 feet, provided an equivalent amount and function of
pervious land is established elsewhere on the property that utilizes water
quality measures including, but not limited to: wetlands; bioswales; and
additional trees, especially in parking areas, exclusive of otherwise
required water quality measures and landscape areas. The applicant has
the burden of proof to demonstrate, to the satisfaction of the Director,
equivalency in relation to both the amount of pervious land (as specified
above) and riparian area function (as specified in SDC 4.3.110(G)).
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 25 of 35
Ordinance No. 6464
Exhibit A Page 26 of 133
(b) An existing building within a riparian area is not considered a non-
conforming use if destroyed by earthquake, flood or other natural
disaster, or fire. In this case, the replacement building may be constructed
within the same footprint as the existing building. If the building is within
the Willamette Greenway, the standards in SDC 3.3.300, Willamette
Greenway Overlay District apply.
(3) Where a watercourse divides a lot/parcel and the existing riparian area along that
watercourse is degraded in riparian function, the applicant may relocate the
watercourse to another portion of the property as approved by the Director and
applicable State or Federal agency.
(8 E) Permitted Uses in Riparian Areas. The following uses are permitted in riparian areas
as long as they do not diminish riparian functions:
(1) The planting of native trees and native vegetation to promote bank stability,
enhance riparian areas, minimize erosion, preserve water quality and protect
federally listed species. Trees may be clustered to allow the preservation of
views; or to allow maintenance vehicles to approach City maintained stormwater
facilities including detention basins, outfalls, culverts and similar stormwater
facilities as may be permitted by the Engineering Design Standards and
Procedures Manual.
(2) The felling of hazardous trees for safety reasons as specified in SDC 5.19.100,
Tree Felling.
(3) Riparian area restoration and enhancement including the removal of invasive
plant species, where necessary.
(4) Flood control structures, where necessary.
(5) Stormwater management systems and outfalls, as specified in the Engineering
Design Standards and Procedures Manual or as required by other regulating
authorities.
(6) Multi-use paths for pedestrian and/or bicycle use must be permitted, provided
that the multi-use path drains away from the watercourse. Multi-use paths must
be located along the outer edge of the required riparian area and away from the
watercourse. The multi-use path must be located at the outermost edge of the
75-foot-wide Riparian Setback to the maximum extent practicable. Utilities may
be extended within a multi-use path.
(7) Water-dependent or water-related uses between the Willamette River and the
Greenway Setback Line as may be permitted in the Willamette Greenway
Overlay District.
(8) Private driveways, public street crossings, bridges, and necessary culverts when
there is no other vehicle access to the property. Crossings must be preferably at
right angles to the watercourse. Public and private utilities must be permitted
within the driveway, public street, or bridge right-of-way.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 26 of 35
Ordinance No. 6464
Exhibit A Page 27 of 133
(9) Repair, replacement, or improvement of utility facilities as long as the riparian
area is restored to its original condition.
(10) Routine repair and maintenance of existing structures, streets, driveways,
utilities, accessory uses and other similar facilities.
(11) Other activities similar to those listed above that do not diminish riparian function.
The Director must make the interpretations as specified in SDC 5.11.100.
(1) inid deV nmt_QAt G_rr-rrt_Qd_t_QV n"reRt lR the fnllGWi�Rg GOFGAHr`�r�r;tta♦p�� p Imo.
(a) Rs IT le areas, ORG1 1doRg, 1961t RGt ImMited CG, 6IRStable slepes, wetlands
'vlRd rrinarian aFeaS; l-Tl
0
(h) Q+ro-Am ('rnccinnc WheFe nrnccinnc haVe +n be nrnVided the imnan+c OR
,
water
11 at er g6iality m1IQ+ be minimiZorJ +n +ho mwim_II-Im-eXteR+ nraGtinal• and
(l+) eRi Rn nr 7rmnrinn of CtY4a7 k Gp�pllptes;
��Prevep GTTII .T r .fin .rnl"f�.T.
(a) Q+nrmHnia+or rlicrhaFge imnan+c to w ateF n1 iality anrd m Ian+ity; anr!
0
(b) ErOssO;-andSed taAt In_n#dI Irinn aPd-;-;fte.r
(3) PFGtesr
(a) parian areas b6i#ers ;anr rnl lnd all Agate nI Irses a,na
(b) Weytlanrl� WL-Qt�nr�I h1lff�c �ndJ Vniet�Ad_ fIInet�ns.
n,. rrcr �P rrcr-aa�T a arrcr-vr r�m-cnT r�r
(i )PFerveFVe-th YdrnI�G GapaGity ofaRY
to Iur
(5) Utilize Native Ve(getat+en in Riparian Areas. The reg6iired ripaFiaR area
(6) Resta-o�d- h�nno rl n7r17n are—asthatare degraded in riparian fl lnetG
(7) In applying cnr 41 3 1 15(Q)('I) +hre Inh (6) riparian area nrn+on+inn nreseryatinn
roc+pro+i FeCn�,n anr•J onh�nromon+ rneaSHFeS m I Ic+ be applied assfnllnnic•
(a) r RAW G1e14 n M en to Rd FedeVelOpMeRt, eX i Sti R i n riaria rrarca faT ct1-rr-
m1 st be pF()tented aR d pFese Fyed [Deg Fade J f1 RGti()roc rvml ist be Feste Fed
nr onhanro`•I +hre Inh the f1 III riparian area width as SpeGifie d in Cflf`
0
it 3 -115(A)(I) aR d (2) and exteR iRg +hFo gh the f1III frP1Y1+age of the
19Vparnol alGRg the w ateFrnl lrce nn the Water I 6iality Limited
\n/�+ornnl lrco (IAQ \n() Maf
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 27 of 35
Ordinance No. 6464
Exhibit A Page 28 of 133
(b)E)F addTtiGRs and eT r„ PGF ' gf a Ire}/r�Fccre)4s"
riparian area fi inrtinns mi ist be nrnterted and nresePied thrni 1gh the fi ill
FipaY,aR aY d e ii OR SDG n 3 115(A)(1) and (2) and + diRg
7�7QT1'GITC.Tr�.G1�V'7QJpcV11fCG Z ,TG'TTCr-�./�CGTIGTTTGJ
thrni 1gh the fi ill frontage of the lnt/naFGel along Oho nn the
WG LVV MaY,
(G) FeY additi E)Rs nrl thin, 100 feet of a ,at G irse OR
t rrvrrs-ancre�C�crmr-rvvzce•�-vr-a=vrcrce�^�ur�c-vrrthe
\nQ VV Map nn a Int/narruel that has degraded riparian fi inntinns the area
far resteratiGR gr enhannement must be baser! i 1PE)R the ratie gf the
imneriini is area of the aAdditinn nr expanslnn to the evicting b lilding nr
imneriini is area nn the Int/nargel The resin rotinn nr enhancement mi ist
start at the inn of hank of the vn,aterr-ni arse and werk landward
Commentary: The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to add
vegetated stormwater facilities in landscaping requirements. SDC 4.4.105 clarifies that Low
Impact Development is a landscaping requirement and must be landscaped to comply with SDC
4.3.110(C) for review under the Treatment Standard. Where parking lot planting areas are
required, Low Impact Development and vegetated structural stormwater controls may be used
to meet that requirement.
Note: Section 4.4.105(E) for Parking Lot landscaping are outside the scope of these Stormwater
Post-Construction Requirements Update amendments but are provided for context and clarity.
4.4.100 - Landscaping, Screening, and Fence Standards
4.4.105 Landscaping.
(A) These regulations ensure that new development complies with the landscaping
provisions of this code and any applicable Refinement Plans, Plan Districts, Master
Plans, and Conceptual Development Plans; is adequately screened from less intensive
development; considers the effects of vegetation on public facilities; retains significant
clusters of natural trees and shrubs wherever possible; minimizes run-off, protects water
quality and moderates temperature: facilitates energy conservation and crime
prevention; and improves the appearance of the City to create a desirable place to live
and work.
(B) Twee Four types of landscaping may be required:
(1) Landscaping standards for private property as specified in this section and
other sections of this code.
(2) Street trees in the public right-of-way as specified in SDC 4.2.140.
(3) Curbside planter strips in the public right-of-way as specified in SDC 4.2.135.
44) Low Impact Development as specified in SDC 4.3.110(Cl for review under the
Treatment Standard.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 28 of 35
Ordinance No. 6464
Exhibit A Page 29 of 133
Fe9 •red by the Mini miirn DeyeiepmeRtS�S SDG � 1F 100 must Rot need 10
r`'`'luir �. �cTc�-vv-rrraa v�e3Ccc Tv
CQ The following areas of a lot/parcel must be landscaped, unless otherwise specified in
this code:
(1) All required setback areas and any additional planting areas as specified in the
appropriate zoning district.
(2) Parking lot planting areas required in this section.
3 Low Impact Development as specified in SDC 4.3.110(C) for review under the
Treatment Standard.
(€ D) At least 65 percent of each required planting area listed in Subsection (D) above must
be covered with living plant materials within 5 years of the date of installation, unless a
higher standard applies elsewhere in this code. The living plant materials must be
distributed throughout the required planting area. The planting acceptable per 1,000
square feet of required planting area is as follows:
(1) A minimum of 2 trees, not less than 6 feet in height, that are at least a 2 inch
(dbh) caliper (at the time of planting, not including root ball); and
(2) Ten shrubs, 5 gallons or larger.
(3) Lawn and/or groundcover may be substituted for up to 25 percent of the living
plant material requirement, unless trees or shrubbery are required for screening.
This substitution is only allowed when the applicant has demonstrated that there
+&-are provisions for ongoing maintenance of the landscape areas.
These standards do not apply to single unit detached dwellings and middle housing in
the R-1 District.
(F- E) Parking Lots. Par ParkiRg ^tPlant� Fea 11stTTG "�� caROPY roe A+ IP—ASt � innhoc
vy Tarr �rcczrc-r�csz�-rcncc
((` bh) O pel- that Mee ity street tree stapdards as may be permitted by
ef-�""�vay OF that 06 -hared rthe Trte lnr of aRY parking 19t HSt RvtexCveedz2.5 feet
height at rnat grit y
M The following Pparking lot planting areas must be landscaped in accordance with
the standards in (21 below include:
(4a) Parking and driveway setback areas specified in the applicable land use
district; and
(2b) Five percent of the interior of a parking lot, exclusive of any required
parking setbacks, if 24 or more parking spaces are located between the
street side of a building and an arterial or collector street and are visible
from any street.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 29 of 35
Ordinance No. 6464
Exhibit A Page 30 of 133
(4c) See also SDC 4.7.380 or4.7.385 for multiple unit housing design
standards.
(2) Parking lot planting areas must include at least 4 shrubs. 5 gallon or larger. for
each 100 square feet of planting area. Any shrubs that abut public right-of-way or
that is placed in the interior of any parking lot must not exceed 2.5 feet in height
at maturity. Where parking lot planting areas are required. Low Impact
Development and vegetated structural stormwater controls may be used to meet
this requirement. Shrubs provided within a structural stormwater control may not
be counted toward meeting this criterion.
L321 Small Parking Lots and Modifications to Existing Parking Lots. Planting
areas for developments with one-half acre or less of new surface parking lot area
must include 1 canopy tree at least 2 inches (dbh) in caliper, for each 100 sauare
feet of parking lot planting area. Trees must meet City street tree standards in
the City of Springfield Street Tree list in Appendix G for the appropriately_ sized
planter area.
4) Large Parking Lots. Developments that include more than one-half acre of
surface parking lot area must comply with the following:
a) Developments not required to comply with OAR 330-135-0010 must
provide a climate mitigation action including at least one of the following:
i) Payment of at least $1500 per new parking space into a fund at
the Oregon Department of Energy dedicated to equitable solar or
wind energy development: or
ii+) Tree canopy covering at least 40% of the new parkins lot area at
maturity but no more than 15 years after planting: or
iii) If parking is provided for a non-residential use, the development
may include a mixture of(i) and (ii) — providing between 30% and
40% tree canopy and paving for a proportionate percentage of
parking spaces.
b) Developments must provide either trees along driveways or a minimum of
30% tree canopy coverage over parking areas. Developments are not
required to provide trees along drive aisles.
c) The tree spacing and species planted must be designed to maintain a
continuous canopy, except when interrupted by driveways, drive aisles,
and other site design considerations. Trees that are provided in
compliance with (4)(a)(ii) above meet this standard.
d) Trees must meet City street tree standards as specified in Citv of
Springfield Street Tree list in Appendix G for the appropriately sized
planter area.
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 30 of 35
Ordinance No. 6464
Exhibit A Page 31 of 133
es) Development of a tree canopy under subsections (a) and (b) must be
done in coordination with the local electric utility, including_ pre-Id
building, and maintenance phases.
fd) Applicant must provide a certification provided by a certified arborist with
an Oregon Landscape Contractor license that trees planted to meet
subsections (1) and (2)will be planted to meet or exceed the 2021
American National Standards Institute A300 standards.
(6 F) All new required planting areas must be provided with a permanent irrigation system
which can include a drip irrigation system. Areas planted with noninvasive drought
tolerant species or plant communities are exempt from this standard.
(#S_a) Landscaped setbacks abutting required screening on the same property are exempted
from planting requirements if the area is not visible from any public right-of-way or
adjacent property.
(f H) Planting Installation Standards.
(1) Existing landscaping to be retained must be provided with protection which will
remain through the construction process. The plants to be saved and the method
of protection must be noted on the Landscape Plan.
(2) Existing trees to be retained on private property must not have construction
occur within the drip line, unless a landscape architect certifies that affected
trees will not have at least a 90 percent chance of survival over a 5-year period.
Trees to be retained must be provided with protection with at least a 3-foot-tall
temporary fence barrier around the drip line and include protection around the
tree to prevent abrasion to the tree. The trees to be retained and the method of
protection must be included on the Landscape Plan.
(3) The Landscape Plan must include specifications for topsoil, including depth and
organic matter requirements, to ensure the health and vitality of required
planting. Where planting areas have been excavated the replacement of topsoil
must be provided for and indicated on the Landscape Plan. All waste material
must be removed from required planting areas prior to the application of topsoil.
(a) Inspection may be made by the Director prior to planting to verify proper
rough grade and installation of irrigation systems.
(b) Plant materials and soil preparation may be inspected prior to or in
conjunction with the occupancy inspection to ensure that placement,
quantity, size, and variety conform to the approved Planting Plan and the
requirements of this section. Nursery tags identifying variety and species
must remain on plant specimens until the Final Building Inspection by the
Building Official or the issuance of a Certificate of Occupancy. (6443)
4 Landscaping and vegetation within structural stormwater controls. including Low
Impact Development. must meet the maintenance requirements in SDC
4.3.110ff .
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 31 of 35
Ordinance No. 6464
Exhibit A Page 32 of 133
Commentary. The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to allow
curb cuts to allow runoff from stormwater quality facilities in parking lot landscaping.
4.6.120 Motor Vehicle Parking—Parking Lot Improvements.
All parking areas must conform to the setback, vision clearance, planting, and screening
provisions of this code and must be completed prior to occupancy. Required parking spaces
must be improved as follows:
(C) All parking spaces fronting a sidewalk, alley, street, landscaped area, or structure must
be provided with a secured wheel bumper or linear curb not less than 6 inches in height
to be set back from the front of the stall a minimum of 2 feet to allow for vehicle
encroachment. Wheel bumpers must be a minimum of 6 feet in length. Curbs must be
constructed in conformance with the Standard Construction Specifications. the curb into
the landscape area. Curbs separating landscaped areas from parking areas must allow
stormwater runoff to pass through, as provided in APWA detail drawing RD RD700
&701.
Commentary. The recommendation to amend this section comes from the City of Springfield
Stormwater Facilities Master Plan (2008) which proposed that the code be amended to require
review for stormwater management requirements or additions and expansions of impervious
areas.
5.17.100 - Site Plan Review
5.17.110 Applicability.
(A) The Site Plan Review process is used for:
(1) The following categories of multiple unit housing, commercial, public and semi-
public, and industrial development or uses, including construction of impervious
surfaces for parking lots-astorage areas, and stormwater improvements:
(a) New development on vacant sites and redevelopment, except:
(i) Where a proposed development qualifies for a Minimum
Development Standards review in accordance with SDC 5.15;
(ii) Where multiple unit housing qualifies for a Type 1 process as
specified in SDC4.7.380.
(b) Additions or expansions that exceed either 50 percent of the existing
building gross floor area or 5,000 square feet or more of new building
gross floor area and/or impervious surface area, except where a
Code Amendments—Legislative Version
Stormwater Post-Construction Requirements Update Page 32 of 35
Ordinance No. 6464
Exhibit A Page 33 of 133
proposed development qualifies for a Minimum Development Standards
review according to SDC 5.15;
(c) Additions, expansions, and changes of use, regardless of size or
intervening use, that:
(i) Contain or are within 150 feet of the top of bank (as measured
from the property line of the subject property) of any Water Quality
Limited Watercourses (WQLW) identified on the WQLW Map on
file in the Development SeFViGes and Public Works Department;
(ii) Contain or are within 100 feet of the top of bank (as measured
from the property line of the subject property) of any direct
tributaries of WQLW identified on the WQLW Map on file in the
Development SerVises and Public Works Department;
(iii) Are located within the City's urbanizable area, outside of the city
limits; or
(iv) Are located within 50 feet of property in a residential land use
district or residentially designated land (as measured from the
property line of the subject property); or
Uv Proposes review under the Treatment Standard in SDC
4.3.110(B)-(C) to demonstrate compliance with applicable
stormwater treatment standards.
(d) Discretionary Uses, except where a proposed development qualifies for a
Minimum Development Standards review in accordance with SDC 5.15;
and
(e) Any uses listed in the applicable land use district, overlay, or plan district,
which specifically require Site Plan Review.
Commentary: Definitions are provided to SDC 6.1.110 to clarify stormwater terms.
6.1.100— Definitions
6.1.110 Meaning of Specific Words and Terms.
Evapotranspiration. The sum of evaporation and transpiration of water from the earth's surface
to the atmosphere. Includes the evaporation of liquid or solid water plus transpiration from
plants (the release of water vapor into the atmosphere through plant stomata or pored.
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Ordinance No. 6464
Exhibit A Page 34 of 133
asphalt paviRg GR walkways, driveways, parkiRg 19tS, gFaVel 'At'-; aAc-d reads; and hea
GGFn aGted earthen materials
Impervious Surface. Any surface resulting from development activities that prevents the
infiltration of water. Common impervious surfaces include: building roofs; traditional concrete or
asphalt paving on walkways, driveways, parking lots, gravel lots and roads; and heavily
compacted earthen materials.
Low Impact Development (LID). A stormwater management approach that seeks to mitigate
the impacts of increased runoff and stormwater pollution using a set of planning, design. and
construction approaches and stormwater management practices that promote the use of natural
systems for infiltration, evapotranspiration, and reuse of rainwater, and can occur at a wide
range of landscape scales (i.e., regional, community, and site). Low impact development is a
comprehensive land planning and engineering design approach to stormwater management
with a goal of mimicking the pre-development hydrologic regime of urban and developing
watersheds.
Off-line Stormwater Facilities. Facilities that are sized for only the water quality_ storm and in
which higher stormwater flows are bypassed around the treatment area. These facilities
typically require an inlet control structure and typically include mechanical treatment facilities.
On-line Stormwater Facilities. Facilities in which stormwater flows are routed through the
treatment area, so high flows are not bypassed around the facility, such as vegetated swales
and most vegetated treatment facilities.
Predevelopment Hydrologic Function. The hydrology of a site reflecting the local rainfall
atterns. soil characteristics, land cover, evapotranspiration. and topoaraphv. The term
redevelopment as used in predevelopment hydrologic function is consistent with the term
redevelopment as discussed in Federal Register Volume 64, Number 235 and refers to the
runoff conditions that exist onsite immediately before the planned development activities occur.
Predevelopment is not intended to be interpreted as the period before any human-induced land
disturbance has occurred.
Storm Event. A precipitation event that results in surface runoff. For modeling purposes in the
City of Springfield this is a Type 1 a storm of 24-hour duration.
management systern.
Stormwater or Stormwater Runoff. That portion of precipitation that does not naturally
percolate into the ground or evaporate, but flows via overland flow, interflow, channels. or pipes
into a defined surface water channel or a constructed infiltration facility. It includes snow melt
runoff and surface runoff and drainage.
Structural Stormwater Controls. Stormwater controls that are physically designed, installed,
and maintained to prevent or reduce the discharge of pollutants in stormwater to minimize the
impacts of stormwater on waterbodies. Examples of structural stormwater controls or Best
Management Practices (BMPs) include: (1) storage practices such as wet ponds and extended-
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Ordinance No. 6464
Exhibit A Page 35 of 133
detention outlet structures: (2) filtration practices such as grassed swales, sand filters and filter
strips: and. (3) infiltration practices such as infiltration basins and infiltration trenches.
Total Maximum Daily Loadings (TMDL). The calculated pollutant amount that a water body
can receive and still meet Oregon water quality standards. The TMDL program evaluates and
sets pollutant loads to impaired waterbodies and designates management agencies to
implement water quality improvement plans.
Total Suspended Solids (TSS). The ratio of the weight of solid residue in a filtered sample to
the volume of the sample, where the residue is obtained by filtering the sample through a 0.45
um filter.
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Ordinance No. 6464
Exhibit A Page 36 of 133
APPENDIX B
SANTA BARBARA URBAN HYDROGRAPHY METHOD
(A) Overview
(1) The Santa Barbara Urban Hydrograph (SBUH) method was developed by the
Santa Barbara County Flood Control and Water Conservation District to
determine a runoff hydrograph for an urbanized area.
(B) Elements Of the Santa Barbara Urban Hydrograph (SBUH) Method
(1) The SBUH method depends on several variables:
(a) Pervious (Ap) and impervious (A;,,,p) land areas
(b) Time of concentration (T,) calculations
(c) Runoff curve numbers (CN) applicable to the site
(d) Design storm
(C) Land Area
(1) The total area, including the pervious and impervious areas within a drainage
basin, shall be quantified in order to evaluate critical contributing areas and the
resulting site runoff.
(2) Each area within a basin shall be analyzed separately and their hydrographs
combined to determine the total basin hydrograph.
(3) Areas shall be selected to represent homogenous land use/development units.
(D) Time of Concentration
(1) Time of concentration, T,, is the time for a theoretical drop of water to travel from
the furthest point in the drainage basin to the facility being designed. (In this
case, T, is derived by calculating the overland flow time of concentration and the
channelized flow time of concentration.) T, depends on several factors, including
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 37 of 133
ground slope, ground roughness, and distance of flow. The following formula for
determining Tc is:
(a) Formulas
(I) T, = Ttj + Tc2 +Tc3 + ... + Tcn
(ii) Tt = L/60V (Conversion of velocity to travel time)
(iii) Tt = (0.42 (nL)08)/(158(s)04) (Manning's kinematic solution for
sheet flow less than 300 feet)
(b) Shallow concentrated flow for slopes less than 0.005 ft/ft.:
(i) V = 16.1345(s)05 (Unpaved surfaces)
(ii) V = 20.3282(s) 0.5 (Paved surfaces)
(c) Where,
(i) Tt = travel time, minutes
(ii) Tc = total time of concentration, minutes (minimum Tc = 5
minutes)
(iii) L = flow length, feet
(iv) V = average velocity of flow, feet per second
(v) n = Manning's roughness coefficient for various surfaces
(vi) s = slope of the hydraulic grade line (land or watercourse slope),
feet per foot
(d) When calculating T,, the following limitations apply:
(i) Overland sheet flow (flow across flat areas that does not form into
channels or rivulets) shall not extend for more than 300 feet.
(ii) For flow paths through closed conveyance facilities such as pipes
and culverts, standard hydraulic formulas shall be used for
establishing velocity and travel time.
(iii) Flow paths through lakes or wetlands may be assumed to be zero
(i.e., T, = 0).
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 38 of 133
(E) Runoff Curve Numbers
(1) The runoff curve numbers approved for water quantity/quality calculations are
included as Table C-2 of this appendix.
(2) The curve numbers presented in Table C-2 are for wet antecedent moisture
conditions. Wet conditions assume previous rainstorms have reduced the
capacity of soil to absorb water. Given the frequency of rainstorms in this area,
wet conditions are most likely and give conservative hydrographic values.
(F) Design Storm
(1) The SBUH method also requires a design storm to perform the runoff
calculations. For flow control calculations, use NRCS Type 1A 24-hour storm
distribution. This storm is shown in Figure C-1 and Table C-4. The depth of
rainfall for the 2 through 100-year storm events is shown below in Table C-1.
Table C-1
24-HOUR RAINFALL DEPTHS
Recurrence Interval, Years 2 5 10 25 100
Flood Control, Destination: 3.12 3.6 4.46 5.18 6.48
24-Hour Depths, Inches
Water Quality Storm— Pollution reduction: 24-Hour Depths, 1.4 Inches
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 39 of 133
Table C-2
Runoff Curve Numbers
Cover Curve numbers for
description hydrologic soil group
Cover type A B C D
Hydrologic
condition
Runoff curve numbers for urban areas*
Open space (lawns, parks, golf courses, cemeteries,etc.):
Grass cover<50% 68
79 86 89
Grass cover 50% to 75%) 49 69 79 84
Grass cover> 75% 39 61 74 80
Impervious areas:
Paved parking lots, roofs, 98 98 98 98
driveways, etc. (excluding right-of-
way)
Streets and roads:
Paved; curbs and storm sewers 98
(excluding right-of-way) 98 98 98
Paved; open ditches (including right-of- 83 89 92 93
way)
Gravel (including right-of-way) 76 85 89 91
Dirt (including right-of-way) Urban 72 82 87 89
districts:
Urban districts:
Commercial and business 89 92 94 95
Industrial 81 88 91 93
Residential districts by average lot size:
1/8 acre or less (town houses) 77 85 90 92
1/4 acre 61 75 83 87
1/3 acre 57 72 81 86
1/2 acre 54 70 80 85
1 acre 51 68 79 84
2 acres 46 65 77 82
Runoff curve numbers for other agricultural lands*
Pasture, grassland, or range-continuous forage for grazing
<50% ground cover or heavily grazed I Poor 68 79 86 89
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 40 of 133
with no mulch
50 to 75% ground cover and not heavily Fair 49 69 79 84
grazed
>75% ground cover and lightly or only Good 39 61 74 80
occasionally grazed
Meadow-continuous grass, protected _ 30 58 71 78
from grazing and generally mowed
for ha
<50% ground cover Poor 48 67 77 83
50 to 75% ground cover Fair 35 56 70 77
>75% ground cover Good 30 48 65 73
Woods-grass combination (orchard or Poor 57 73 82 86
tree farm
Fair 43 65 76 82
Good 32 58 72 79
Woods
Forest litter, small trees, and
brush are destroyed by heavy Poor 45 66 77 83
grazing or regular burning.
Woods are grazed but not burned, and Fair 36 60 73 79
some forest litter covers the soil.
Woods are protected from grazing, and Good 30 55 70 77
litter and brush adequately cover the
soil.
Runoff curve numbers for Simplified Approaches"
Eco-roof
Good n/a 61 n/a n/a
Roof Garden Good n/a 48 n/a n/a
Contained Planter Box Good n/a 48 n/a n/a
Infiltration & Flow-Through Planter Box Good n/a 48 n/a n/a
Pervious Pavement - 76 85 89 n/a
Trees
New and/or Existing Evergreen - 36 60 73 79
New and/or Existing - 36 60 73 79
Deciduous
n/a - Does not apply,as design criteria for the relevant mitigation measures do not include
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 41 of 133
the use of this soil type.
*Soil Conservation Service, Urban Hydrology for Small Watersheds,Technical Release 55,
pp. 2.5-2.8, June 1986.
**CNs of various cover types were assigned to the Proposed Simplified Approaches
with similar cover types as follows:
Eco-roof—assumed grass in good condition with soil type B.
Roof Garden—assumed brush-weed-grass mixture with >75%ground cover and
soil type B. Contained Planter Box—assumed brush-weed-grass mixture with
>75%ground cover and soil type B.
Infiltration &Flow-Through Planter Box—assumed brush-weed-grass mixture
with >75% ground cover and soil type B.
Pervious Pavement—assumed gravel.
Trees—assumed woods with fair hydrologic conditions.
Note: To determine hydrologic soil type,consult local USDA Soil
Conservation Service Soil Survey.
Table C-3
NRCS Hydrologic Soil
Group Descriptions
NRCS Hydrologic
Soil Group Description
Group A Soils having a high infiltration rate (low runoff potential)when
thoroughly wet. These consist chiefly of deep,well drained to
excessively drained sands or gravels. These soils have a high
rate of water transmission.
Group B Soils having a moderate infiltration rate when thoroughly wet.
These consist chiefly of moderately deep or deep, moderately
well drained or well drained soils that have moderately fine
texture to moderately coarse texture. These soils have a
moderate rate of water transmission.
Group C Soils having a slow infiltration rate when thoroughly wet. These
consist chiefly of soils that have a layer that impedes the
downward movement of water or soils that have a moderately
fine texture. These soils have a slow rate of water transmission.
Group D Soils having a very slow infiltrate rate (high runoff potential)
when thoroughly wet. These consist chiefly of clay soils that
have a high shrink-swell position, soils that have a permanent
high water table, soils that have a fragipan or clay layer at or
near the surface, and soils that are shallow over nearly
impervious material. These soils have a very slow rate of water
transmission.
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 42 of 133
Figure C-4 MRCS 24-H our Type 1A Hyetograph
6.00 120
6.00 100
m
E 4.00 80
j
v 3.00 '" 60 c
+• w
m �
IL
2.00 40 0
U
1.00 20
�Time Start of Storm, Min tes
0.00 0
0 200 400 600 800 1,000 1,200 1,400 1,600
Appendix B—Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 43 of 133
Table C-5-NRCS Type 1A tjyetipg,rppftjq, Distribution - For Use In Water Quality/Quantity
Design
Time From Time From QUA- Time From Time From W#W-
Start of lative Start of lative Start of lative Start of lative
Storm, % :k-c Storm: % % Storm. % % storm: % %
Minutes Rainfall 8,qlA!n Minutes Rainfall Rpj" Minutes Rainfall E(qM Minutes Rainfall RACf4
0 - 10 0.40 0.4C 360 - 370 0.95 22.57 720 - 730 032 67.40 1080- 1090 0.40 96.0c
10 - 20 0.40 0.3c 370 - 330 0.95 23.52 730 - 740 032 63.12 1090- 1100 0.40 86.4C
20 - 30 0.40 1.2C 380 - 390 0.95 24.47 740 - 750 0.72 63.84 1100- 1110 0.40 86.8c
30 - 40 040 1_6C 390 - 400 0.95 25.42 750 - 760 0.72 69.56 1110- 1120 0.40 87.2 C
40 - 50 0.40 2.0C 400 - 410 1.34 26.76 760 - 770 0.57 70.13 1120- 1130 0.40 87.6 C
50 - 60 040 24C 410 - 420 1.34 28.10 770 - 730 0.57 70.70 1130- 1140 0.40 88.0c
60 - 70 0.40 2.8C 420 - 430 1.34 29.44 780 - 790 0.57 71.27 1140- 1150 0.40 98.4C
70 - 80 040 32C 430 - 440 1.80 31.24 790 - 800 057 71.84 1150- 1160 0.40 88.8c
30 - 90 0A0 16C 440 - 450 1.80 33.04 800 - 810 0.57 72.41 1160- 1170 0.40 89.2 C
90 - 100 040 4_10C 450 - 460 3.40 36.44 810 - 820 057 72.98 1170- 1130 0.40 89.6 C
100 - 110 0.50 4.5C 460 - 470 5.40 41.84 820 - 830 0.57 73.55 1190- 1190 0.40 90.0c
110 - 120 0.,50 5.0c 470 - 400 2.70 44.54 830 - 040 0.57 74.12 1190- 1200 0.40 90.4 C
120 - 130 050 5-5c 480 - 490 1.80 45.34 840 - 850 057 74.69 1200- 1210 0.40 90-8C
130 - 140 0.50 6.0c 490 - 500 1.34 47.68 850 - 860 0.57 75.26 1210- 1220 0.40 91.2 C
140 - 150 050 6-5c 500 - 510 1.34 49.02 860 - 870 057 75.83 1220- 1230 0.40 9115C
150 - 160 050 7_0C 510 - 520 1.34 50.36 870 - 880 057 76.40 1230- 1240 0.40 92-0C
160 - 170 0.60 7.6C 520 - 530 0.88 51.24 Goo - 890 0.50 76.90 1240- 1250 0.40 92.4 C
170 - 180 060 82C 530 - 540 0.88 52.12 890 - 900 050 77.40 1250- 1260 0.40 92-8C
180 - 190 0.60 8.3c 540 - 550 0.88 53.00 900 - 910 0.50 77.90 1260- 1270 0.40 93.2 C
190 - 200 060 9AC 550 - 560 0.88 53.88 910 - 920 050 73.40 1270- 1280 0.40 93.6c
200 - 210 0.60 10.0C 560 - 570 0.88 54.76 920 - 930 0.50 73.90 1280- 1290 0.40 94.0C
210 - 220 0.60 10.6C 570 - 580 0.88 55.64 930 - 940 0.50 79.40 1290- 1300 0.40 94.4 C
220 - 230 070 11_3C 580 - 590 0.88 56.52 940 - 950 050 79.90 1300- 1310 0.40 91.9 C
230 - 240 0.70 12.0C 590 - 600 0.88 57.40 950 - 960 0.50 80.40 1310- 1320 0.40 95.2 C
240 - 250 070 12_7C 600 - 610 0.88 58.28 960 - 970 050 80.90 1320- 1330 0.40 956C
2.50 - 260 0.70 13.4C 610 - 620 0.88 59.16 970 - 980 0.50 31.40 1330- 1340 0.40 96.0c
260 - 270 070 14AC 620 - 630 0.88 60.04 980 - 990 050 91.90 1340- 1350 0.40 964C
270 - 280 0.70 14.30 630 - 640 0.88 60.92 990 - 1000 0.50 82.40 1350- 1360 0.40 96.3c
280 - 290 032 15.62 640 - 650 0.72 61.64 1000 - 1010 040 82.80 1360- 1370 0.40 972C
290 - aOO 0.82 16A4 650 - 660 0.72 62.36 1010 - 1020 0.40 83.20 1370- 1330 0.40 97.6 C
300 - 310 032 1726 660 - 670 0.72 63.08 1020 - 1030 040 83.60 1390- 1390 0.40 98-0C
310 - 320 032 18-0E 670 - 690 0.72 63.80 1030 - 1040 040 84.00 1390- 1400 0.40 984C
320 - 330 0.82 18.9C 680 - 690 0.72 64.52 1040 - 1050 0.40 84.40 1400- 1410 0.40 98.3c
330 - 340 032 1972 690 - 700 0.72 65.24 1050 - 1060 040 84.80 1410- 1420 0.40 992C
340 - 350 095 2067 700 - 710 0.72 65.96 1060 - 1070 040 85.20 1420- 1430 0.40 996c
350 - 360 0.95 21.62 1 710 - 720 0.72 66.68 1 1070 - 1030 0.40 95.60 1 1430- 1440 0.40 100.0
Appendix B-Santa Barbara Urban Hydrograph Method
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 44 of 133
APPENDIX C
INFILTRATION TESTING
(A) Applicability
(1) To properly size and locate stormwater management facilities, it is necessary to
characterize the soil infiltration conditions at the location of the proposed facility.
All projects that propose onsite infiltration must evaluate existing site conditions
and determine:
(a) If the infiltration rate is adequate to support the proposed stormwater
management facility (satisfied through presence of mapped NRCS Type
A& B Soils or the Simplified Approach infiltration test) or;
(b) The design infiltration rate prior to facility design (satisfied through the
Presumptive Approach infiltration testing conducted by a qualified
professional).
The following sections provide the approved standard infiltration testing specifications.
(B) Simplified Approach Open Pit Infiltration Test
(1) The purpose of the Simplified Approach is to provide a method which can be
conducted by a nonprofessional for design of simple stormwater systems on
small projects.
(2) The Simplified Approach open pit test is applicable only to projects on private
property with less than 15,000 square feet of new or redeveloped impervious
area.
(a) The results of infiltration testing must be documented on the Simplified
Approach Form.
(b) The Simplified Approach cannot be used to find a design infiltration rate.
(c) The intent of the open pit test is to determine whether or not the local
infiltration rate is adequate (2 inches/hour or greater) for the predesigned
stormwater facilities described in Appendix F of the EDSPM(Infiltration
swales, basins, planters, drywells, and trenches).
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 45 of 133
(d) The Simplified Approach Infiltration Test does not need to be conducted
by a licensed professional.
(C) Simplified Approach Procedure
(1) A simple open pit infiltration test is required for each facility designed through the
Simplified Approach. The test should be where the facility is proposed or within
the immediate vicinity.
(a) Excavate a test hole to the depth of the bottom of the infiltration system,
or otherwise to 4 feet.
(i) The test hole can be excavated with small excavation equipment
or by hand using a shovel, auger, or post hole digger.
(ii) If a layer hard enough to prevent further excavation is
encountered, or if noticeable moisture/water is encountered in the
soil, stop and measure this depth from the surface and record it on
the Simplified Approach Form. Proceed with the test at this depth.
(iii) Fill the hole with water to a height of about 6 inches from the
bottom of the hole, and record the exact time. Check the water
level at regular intervals (every 1 minute for fast draining soils to
every 10 minutes for slower-draining soils) for a minimum of 1
hour or until all of the water has infiltrated. Record the distance the
water has dropped from the top edge of the hole.
(iv) Repeat this process two more times, for a total of three rounds of
testing.
(v) These tests should be performed as close together as possible to
accurately portray the soil's ability to infiltrate at different levels of
saturation. The third test provides the best measure of the
saturated infiltration rate.
(b) For each test pit required, submit all three testing results with the date,
duration, drop in water height, and conversion into inches per hour.
(c) If the results of the Simplified Approach open pit test show an infiltration
rate greater than 2.0 inches per hour, the applicant can proceed with
Simplified Approach facility design (where applicable).
(d) If the applicant would like to use an infiltration rate for design purposes, a
Presumptive Infiltration Test must be conducted.
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 46 of 133
(D) Presumptive Infiltration Testing
(1) The Presumptive Approach must be used for all public and private developments
where the Simplified Approach is not applicable.
(2) The qualified professional must exercise judgment in the selection of the
infiltration test method.
(3) The three infiltration available testing methods used to determine a design
infiltration rate are:
(a) Open pit falling head;
(b) Encased falling head; or
(c) Double-ring infiltrometer.
(4) Where satisfactory data from adjacent areas is available that demonstrates
infiltration testing is not necessary, the infiltration testing requirement may be
waived.
(5) Waiver of the site specific testing is subject to approval by the City.
(6) Recommendation for foregoing infiltration testing must be submitted in a report
which includes supporting data and is stamped and signed by the project
engineer or geologist.
(E) Testing Criteria
(1) Except for the Simplified Approach, all testing must be conducted or overseen by
a qualified professional who is either a Professional Engineer, Registered
Geologist, Soil Scientist or other professional testing service with equivalent
training and experience in determining the permeability of soils.
(2) The depth of the test must correspond to the facility depth.
(a) If a confining layer is observed during the subsurface investigation to be
within 4 feet of the bottom of the planned infiltration system, the testing
should be conducted within that confining layer.
(b) Tests must be performed in the immediate vicinity of the proposed facility.
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 47 of 133
(c) Exceptions can be made to the test location provided the qualified
professional can support that the strata are consistent from the proposed
facility to the test location.
(d) Infiltration testing should not be conducted in engineered or
undocumented fill.
(F) Minimum Number of Required Tests
(1) The simplified Approach requires one infiltration test for every proposed facility.
(2) The Presumptive Approach requires one infiltration test for every proposed
facility or one test for every 100 feet of proposed linear facility.
(3) Generalized soil infiltration rates may be used if facilities are proposed in areas of
consistent topography and soil strata as outlined in a Geotechnical report.
(G) Factor of Safety
(1) A minimum factor of safety of 2 shall be applied to field obtained infiltration rates
where infiltration of the site performance standard storm per 4.3.110 (B) is
proposed.
(H) Presumptive Infiltration Testing Instructions
Open Pit Falling Head Procedure
The open pit falling head procedure is performed in an open excavation and therefore is
a test of the combination of vertical and lateral infiltration.
(1) Excavate a hole with bottom dimensions of approximately 2 feet by 2 feet into the
native soil to the elevation of the proposed facility bottom. Smooth excavations
should be scratched and loose material removed.
(2) Fill the hole with clean water a minimum of 1 foot above the soil to be tested, and
maintain this depth of water for at least 4 hours (or overnight if clay soils are
present) to presoak the native material.
(a) In sandy soils with little or no clay or silt, soaking is not necessary.
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 48 of 133
(b) If after filling the hole twice with 12 inches of water, the water seeps
completely away in less than 10 minutes, the test can proceed
immediately.
(3) Determine how the water level will be accurately measured. The measurements
should be made with reference to a fixed point.
(4) After the presaturation period, refill the hole with water to 12 inches above the
soil and record the time.
(a) Alternative water head heights may be used for testing provided the
presaturation height is adjusted accordingly.
(b) Measure the water level at 10-minute intervals for a total period of 1 hour
(or 20-minute intervals for 2 hours in slower soils) or until all of the water
has drained.
(c) In faster draining soils (sands and gravels), it may be necessary to
shorten the measurement interval in order to obtain a well-defined
infiltration rate curve.
(d) Constant head tests may be substituted for falling head tests at the
discretion of the professional overseeing the infiltration testing.
(5) Repeat the test.
(a) Successive trials should be run until the percent change in measured
infiltration rate between two successive trials is minimal.
(b) The trial should be discounted if the infiltration rate between successive
trials increases.
(c) At least three trials must be conducted. After each trial, the water level is
readjusted to the 12 inch level.
(6) The average infiltration rate over the last trial should be used to calculate the
unfactored infiltration rate. The final rate must be reported in inches per hour.
(7) For very rapidly draining soils, it may not be possible to maintain a water head
above the bottom of the test pit. A rate based test may be used if the infiltration
rate meets or exceeds the flow of water into the test pit.
Note that a maximum infiltration rate of 20 inches per hour can be used in stormwater
system design.
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 49 of 133
(1) Encased Falling Head Test
The encased falling head procedure is performed with a 6-inch casing that is embedded
approximately 6 inches into the native soil. The goal of this field test is to evaluate the
vertical infiltration rate through a 6-inch plug of soil, without allowing any lateral
infiltration. The test is not appropriate in gravelly soils or in other soils where a good seal
with the casing cannot be established.
(1) Embed a solid 6-inch diameter casing into the native soil at the elevation of the
proposed facility bottom. Ensure that the embedment provides a good seal
around the pipe casing so that percolation will be limited to the 6-inch plug of the
material within the casing.
(a) This method can also be used when testing within hollow stem augers,
provided the driller and tester are reasonably certain that a good seal has
been achieved between the soil and auger.
(3) Fill the pipe with clean water a minimum of 1 foot above the soil to be tested, and
maintain this depth for at least 4 hours (or overnight if clay soils are present) to
presoak the native material.
(a) Any soil that sloughed into the hole during the soaking period should be
removed.
(b) In sandy soils with little or no clay or silt, soaking is not necessary.
(c) If after filling the hole twice with 12 inches of water, the water seeps
completely away in less than 10 minutes, the test can proceed
immediately.
(4) To conduct the first trial of the test, fill the pipe to approximately 12 inches above
the soil and measure the water level.
(a) Alternative water head heights may be used for testing provided the
presaturation height is adjusted accordingly.
(b) The level should be measured with reference to a fixed point. Record the
exact time.
(c) Measure the water level at 10-minute intervals for a total period of 1 hour
(or 20-minute intervals for 2 hours in slower soils) or until all of the water
has drained.
(d) In faster draining soils (sands and gravels), it may be necessary to
shorten the measurement interval in order to obtain a well-defined
infiltration rate curve.
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 50 of 133
(i) Constant head tests may be substituted for falling head tests at
the discretion of the professional overseeing the infiltration testing.
(ii) Successive trials should be run until the percent change in
measured infiltration rate between two successive trials is
minimal.
(iii) The trial should be discounted if the infiltration rate between
successive trials increases.
(iv) At least three trials must be conducted.
(v) After each trial, the water level is readjusted to the 12 inch level.
(vi) The average infiltration rate over the last trial should be used to
calculate the unfactored infiltration rate.
(vii) Alternatively, the infiltration rate measured over the range of water
head applicable to the project stormwater system design may be
used at the discretion of the professional overseeing the testing.
(viii) The final rate must be reported in inches per hour.
(J) Double Ring Infiltrometer Test
(1) The double-ring infiltrometer test procedure should be performed in accordance
with ASTM 3385-94.
(2) The test is performed within two concentric casings embedded and sealed to the
native soils. The outer ring maintains a volume of water to diminish the potential
of lateral infiltration through the center casing. The volume of water added to the
center ring to maintain a static water level is used to calculate the infiltration rate.
(3) The double-ring infiltrometer is appropriate only in soils where an adequate seal
can be established.
(K) Reporting Requirements
The following information should be included in the Infiltration Testing Report. The
Infiltration Testing Report should be attached to the project's Stormwater Management
Report:
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 51 of 133
(1) Statement of project understanding (proposed stormwater system).
(2) Summary of subsurface conditions encountered.
(3) Summary of infiltration testing including location and number of tests and testing
method used.
(4) Discussion of how the tests were performed (i.e. pipe type or diameter or test pit
dimensions).
(5) Infiltration testing results in inches per hour.
(6) Recommended design infiltration rate including factors of safety.
(7) Groundwater observations within exploration and an estimate of the depth to
seasonal high groundwater.
(8) Site plan showing location of infiltration tests.
(9) Boring or test pit logs.
(a) The logs should include an associated soil classification consistent with
ASTM D2488-00, Standard Practice for Classification for Description and
Identification of Soils (Visual-Manual Procedure).
(b) The logs should also include any additional pertinent subsurface
information, such as soil moisture conditions, depth and description of
undocumented or engineered fill, soil color and mottling conditions, soil
stiffness or density, and approximate depth of contact between soil types.
(10) Infiltration Test Data
Appendix C—Infiltration Testing
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 52 of 133
APPENDIX D
TYPICAL FACILITY DETAILS
Ordinance No. 6464
r PAVERS
a z ,
1"WASHED SAND OR SMALL
o f :i?K°' t fix' . r::�::"✓a> g•;r? S;e a DIAMETER AGGREGATE FOR
w BEDDING MATERIAL AS REQUIRED
0 0 0 0 0 o GEOTEXTILE AS REQUIRED BY
THE MANUFACTURER
6" MINIMUM OPEN-GRADED
BASE MATERIAL,'V-2"
CRUSHED-WASHED
-GEOTEXTILE
�SUBGRADE
PERMEABLE CONCRETE BLOCK
OR"PAVER" SYSTEMS
2i, i „ ... - `r''•... OPEN-GRADED
PAVEMENT MIX
6"OPEN-GRADED BASE
MATERIAL, Y4"-2"
CRUSHED-WASHED
GEOTEXTILE
M, -SUBGRADE
PERVIOUS (OPEN GRADED) CONCRETE
AND ASPHALT
PERMEABLE PAVEMENT
TYPICAL DETAILS
o 0
5 FT MIN, 12 FT MAX
FOR PARKING LOTS,
TIRE STOPS OR
3:1 MAX. 2 FT MIN p CURBS WITH CUT OUTS
SIDE SLOPES FLAT BOTTOM
MID.) OVERFLOW
ELEVATION
e
12° \GROWING r�
FILTER FABRIC
OVERFLOW TO APPROVED EXISTING SUBGRADE'
DISCHARGE POINT
1. Provide protection from all vehicle traffic,equipment staging, 7.A geotextile is required to isolate the drain rock from the
and foot traffic in proposed infiltration areas prior to,during, subgrade and growing medium.
and after construction.
2.Dimensions:
a.Width of Swale: 5'-12'. 8. Growing medium:
Depth of Swale: 12" a. In 0-2 year TOTZ,a 24"minimum with at least 50%
b.Longitudinal slope of Swale: 0.5%min and 6%max. organic material
c.Flat bottom width:2'minimum. b. In all other areas, 12"minimum
d.Side slopes of Swale: 3:1 maximum. c. Import topsoil or amended native soil
3.Setbacks(from centerline of facility): 9.Vegetation: Follow landscape plans otherwise refer to plant
a.Infiltration swales must be 10'from foundations and list in SWMM Appendix F. Vegetative swales must have
5'from property lines. following plantings per 100sf of facility area:
b.Filtration swales must have a waterproof liner when a.100 Ground Covers,OR
within 10'from foundation of 5'from property lines. b.80 Ground Covers,2 Small Shrubs,4 Large Shrubs,
and 1 Tree(deciduous or evergreen)
4.Overflow:
a.Overflows are required to an approved point 10. Waterproof liner: Shall be 30 mil PVC or equivalent for
discharge point unless sized to fully infiltrate the flow-through facilities.
flood control design storm.
b.Inlet elevation must allow for 2"of freeboard, 11. Install washed pea gravel or river rock to transition from
minimum. inlets and splash pad to growing medium.
5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of 12. Check dams:Shall be placed at 12"intervals along the
impervious area,otherwise 4"min. Piping material,slopes length of the Swale.
and installation shall follow the Uniform Plumbing Code.
6.Drain rock:
a.Size: 3/4"-2-1/2"washed
b.Depth: 12"minimum
VEGETATED SWALE
TYPICAL DETAILS
Ordinance o. 6464
0
A k
5 Fr MIN, 12 FT MAX
FOR PARKING LOTS,
TIRE STOPS OR
4:1 MAX. 2 FT MIN a
o CURBS WITH CUT OUTS
SIDE SLOPES FLAT BOTTOM
OVERFLOW
ELEVATION
12*
FILTER FABRIC
OVERFLOW TO APPROVED EXISTING SUBGRADE',
DISCHARGE POINT
1. Provide protection from all vehicle traffic,equipment staging, 5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of
and foot traffic in proposed infiltration areas prior to,during, impervious area, otherwise 4"min. Piping material,slopes
and after construction. and installation shall follow the Uniform Plumbing Code.
2.Dimensions: 6. Growing medium:
a.Width of swale:5'-12'. a. In 0-2 year TOTZ,a 24"minimum with at least 50%
Depth of swale: 12" organic material
b.Longitudinal slope of swale: 0.5% min and 6%max. b. In all other areas, 12"minimum
c. Bottom width:2'minimum. c. Import topsoil or amended native soil
d.Side slopes:3:1 maximum for vegetative and 4:1 for 7.Vegetation: Follow landscape plans otherwise refer to plant
grassy.
list in SWMM Appendix F. Grassy swales must have 100
3.Setbacks(from centerline of facility): coverage. Vegetative swales must have following plantings
a.Infiltration swales must be 10'from foundations and per 100sf of facility area:
5'from property lines. a.100 Ground Covers, OR
b.Filtration swales must have a waterproof liner when b.80 Ground Covers,2 Small Shrubs,4 Large Shrubs,
within 10'from foundation of 5'from property lines. and 1 Tree(deciduous or evergreen)
4.Overflow: 8. Waterproof liner:Shall be 30 mil PVC or equivalent where
a.Overflows are required to an approved point required.
discharge point unless sized to fully infiltrate the g. Install washed pea gravel or river rock to transition from
flood control design storm. inlets and splash pad to growing medium.
b.Inlet elevation must allow for 2"of freeboard,
minimum. 10. Check dams:Shall be placed at 12"intervals along the
length of the swale.
GRASSY SWALE
TYPICAL DETAILS
Ordinance o. 6464
BUILDING
FOUNDATION
24"MIN WIDTH
LINER (WHERE REQUIRED)
r 11 DOWNSPOUT
OVERFLOW
Q OVERFLOW
2" o ELEVATION ° °o
0 0 0 o STRUCTURAL WALLS
0 0 p
0 0 0 0
0 0
GRAVEL/SPLASH BLOCK
FILTER FABRIC (WHERE DRAIN ROCK
12" \GROWING MED M \ LAYER IS SPECIFIED)
12" (3/4"TO 2-1/21 WASHED
12"MIN DRAIN ROCK DRAIN ROCK
30 MIL PVC LINER OR EQUIVALENT
ABOVE PLANTER BASE
OVERFLOW AND DRAIN PIPING PERFORATED PIPE
TO APPROVED DISCHARGE POINT TO RUN LENGTH OF
PLANTER
WATERPROOF
WALL AND LINER PENETRATION IXISTING SUBGRADE
1. Provide protection from all vehicle traffic,equipment staging, 6.Drain rock:
and foot traffic in proposed infiltration areas prior to,during, a.Size: 3/4"to 2-1/2" diameter open graded
and after construction. b.Depth: 12"Minimum
c. Length and Width: Full length and width of facility
2.Dimensions:
a.Width of planter:24"minimum. 7.Drain rock layer shall be separated from the growing medium
b.Depth of planter:6"minimum from top of growing by a geotextile
medium to overflow elevation.
c.Slope of planter:0.5%or less. 8.Growing medium:
a. In 0-2 year TOTZ,a 24"minimum with at least 50%
3.Setbacks: organic material
a.Infiltration planters must be 10'from foundations b. In all other areas, 12"minimum
and 5'from property lines. c. Import topsoil or amended native soil
b.Filtration planters do not require a setback with an
approved waterproof liner. 9.Vegetation: Follow landscape plans otherwise refer to plant
list in SWMM Appendix F. Number of plantings per 100sf of
4.Overflow: facility area:
a.Overflows are required to an approved discharge a.100 Ground Covers, OR
point when using the Simplified Method b.80 Ground Covers and 4 Small Shrubs, OR
b.Overflows are not required when sized to fully c.60 Ground Covers and 12 Small Shrubs
infiltrate the flood control event using the
Presumptive Method. 10. Planter walls:
c.Minimum v freeboard from overflow elevation to a.Material shall be stone,brick,concrete,wood,or
the top of the planter walls. other durable material(no chemically treated wood).
b.Walls shall be included on building plans here
5.Piping: Minimum 3"pipe required for u to 1,500 s ft of incorporated into foundations or other permitted
p g� p p q p q
impervious area,otherwise 4"min. Piping material,slopes structures..
and installation shall follow the Uniform Plumbing Code. 11. Waterproof liner(where required):Shall be 30 mil PVC or
equivalent.
12. Install washed pea gravel or river rock to transition from inlet
or splash pad to growing medium.
FOUNDATION
FILTRATION PLANTER
TYPICAL DETAILS
2° OVERFLOW
- —_ —_ — OVERFLOW I—III—III—III-_ DOWNSPOUT OR OTHER
° 0 ELEVATION ° ° o III=III- CONVEYANCE SYSTEM
I 1=1 I I 0 0 ° __ 0 0
12" MAX 'I I o o 0 0
o
GRAVEL OR SPLASH BLOCK
12" MIN GROWING MEDIUM%\/ \\ STRUCTURAL WALLS
FILTER FABRIC
12" MIN
III-I I k-'I El I I %" TO 2-1/2" WASHED DRAIN ROCK
-
-no
—'II I-I 11-
-III=11 k
PERFORATED PIPE TO RUN I 1(—
OVERFLOW TO APPROVED THE LENGTH OF PLANTER SUB-GRADE OR
DISCHARGE POINT EXISTING SOIL
1. Provide protection from all vehicle traffic,equipment staging, 6.Drain rock:
and foot traffic in proposed infiltration areas prior to,during, a.Size: 3/4"to 2-1/2" diameter open graded
and after construction. b. Depth: 12"Minimum
c. Length and Width: Full length and width of facility
2.Dimensions:
a.Width of planter:24"minimum. 7.Drain rock layer shall be separated from the growing medium
b.Depth of planter:6"minimum from top of growing by a geotextile filter fabric
medium to overflow elevation.
c. Slope of planter:0.5%or less.
8.Growing medium:
3.Setbacks: a. In 0-2 year TOTZ,a 24"minimum with at least 50%-
a.Infiltration planters must be 10'from foundations organic material-
and 5'from property lines. b. In all other areas, 12"minimum—
b.Filtration planters do not require a setback with an c. Import topsoil or amended native soil.
approved waterproof liner. 9.Vegetation: Follow landscape plans otherwise refer to plant
list in SWMM Appendix F. Minimum container size is 1 gallon.
4.Overflow: #of plantings per 100sf of facility area:
a.Overflows are required to an approved discharge a.100 Ground Covers, OR
point when using the Simplified Method b.80 Ground Covers and 4 Small Shrubs,OR
b.Overflows are not required when sized to fully c.60 Ground Covers and 12 Small Shrubs
infiltrate the flood control event using the
Presumptive Method. 10. Planter walls:
c. Minimum 2"freeboard from overflow elevation to a.Material shall be stone,brick,concrete,wood,or
the top of the planter walls. other durable material(no chemically treated wood).
b.Walls shall be included on building plans here
5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of incorporated into foundations or other permitted
impervious area,otherwise 4"min. Piping material,slopes structures..
and installation shall follow the Uniform Plumbing Code.
11. Waterproof liner(where required): Shall be 30 mil PVC or
equivalent.
12. Install washed pea gravel or river rock to transition from inlet
or splash pad to growing medium.
FILTRATION PLANTER
TYPICAL DETAILS
OVERFLOW
2°
OVERFLOW I—III—III—III-_ DOWNSPOUT OR OTHER
0 0 0 ELEVATION ° ° o III=III— ��CONVEYANCE SYSTEM
=1 I =III ° -
12" MAX 11= oo o
=I�I-
/ GRAVEL OR SPLASH BLOCK
STRUCTURAL WALLS
12" MIN \\ /\ GROWING MEDIUM' \
- I I-I I I-I I I-
=1�I=ICI=ICI=ICI=ICI=ICI=ICI=ICI-ICI-ICI-
��-IiI-TI-ICI-I��-Iil-I�1-ICI=ICI=1�
OVERFLOW TO APPROVED SUB-GRADE OR
DISCHARGE POINT EXISTING SOIL
1. Provide protection from all vehicle traffic,equipment staging, 5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of
and foot traffic in proposed infiltration areas prior to,during, impervious area,otherwise 4"min. Piping material,slopes
and after construction. and installation shall follow the Uniform Plumbing Code.
2.Dimensions: 6.Growing medium:
a.Width of planter:24"minimum. a. In 0-2 year TOTZ,a 24"minimum with at least 50%
b.Depth of planter:6"minimum from top of growing organic material
medium to overflow elevation. b. In all other areas, 12"minimum
c.Slope of planter:0.5%or less. c. Import topsoil or amended native soil
3.Setbacks: 7.Vegetation: Follow landscape plans otherwise refer to plant
a.Infiltration planters must be 10'from foundations list in SWMM Appendix F. Minimum container size is 1 gallon.
and 5'from property lines. #of plantings per 100sf of facility area:
b.Filtration planters do not require a setback with an a.100 Ground Covers, OR
approved waterproof liner. b.80 Ground Covers and 4 Small Shrubs,OR
c.60 Ground Covers and 12 Small Shrubs
4.Overflow:
a.Overflows are required to an approved discharge 8. Planter walls:
point when using the Simplified Method a.Material shall be stone,brick, concrete,wood,or
b.Overflows are not required when sized to fully other durable material(no chemically treated wood).
infiltrate the flood control event using the b.Walls shall be included on building plans here
Presumptive Method. incorporated into foundations or other permitted
c.Minimum 2"freeboard from overflow elevation to structures..
the top of the planter walls.
9. Install washed pea gravel or river rock to transition from inlet
or splash pad to growing medium.
INFILTRATION PLANTER
TYPICAL DETAILS
D
o Q
TIRE STOPS OR
CURBS CUTS FOR
3:1 MAX. PARKING LOTS
SIDE SLOPES 2 FT MINa
FLAT BOTTOM OVERFLOW
( ) ELEVATION
2'
\/ I
1Y MAX
1Y AIN1
0
� 0 0
12',MIN ) DRAIN ROCK p
/ Q
FILTER FABRIC
OVERFLOW TO APPROVED
DISCHARGE POINT
1. Provide protection from all vehicle traffic,equipment staging, 6.Drain rock:
and foot traffic in proposed infiltration areas prior to,during, a.Size:3/4"-2-1/2"washed
and after construction. b.Depth: 12"Minimum
2.Dimensions: 7.Drain rock later shall be separated form the growing medium
a.Depth of rain garden:6"minimum and 12"maximum and the surround soils by a geotextile filter fabric.
b.Flat bottom width:2'min.
c. Side slopes of Rain Garden: 3:1 maximum. 8.Growing medium:
a. In 0-2 year TOTZ,a 24"minimum with at least 50%
3.Setbacks: organic material
a.Infiltration rain gardens must be 10'from b. In all other areas, 12"minimum
foundations and 5'from property lines. c. Import topsoil or amended native soil
Filtration Rain Garden do not require a setback with
an approved waterproof liner. 9.Vegetation: Follow landscape plans otherwise refer to plant list in
SWMM Appendix F. Number of plantings per 100sf of facility area:
4.Overflow: a.100 Ground Covers, OR
a.Overflows are required unless sized to fully infiltrate b.80 Ground Covers,2 Large Shrubs 4 Small Shrubs
the flood control design storm. and 1 tress(deciduous or evergreen)
b.Inlet elevation must allow for 2"of freeboard,
minimum. 10. Install washed pea gravel or river rock to transition from
inlets and splash pad to growing medium.
5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of
impervious area,otherwise 4"min. Piping material, slopes
and installation shall follow the Uniform Plumbing Code.
FILTRATION RAIN GARDEN
TYPICAL DETAILS
o Q
TIRE STOPS OR
CURBS CUTS FOR
3:1 MAX. PARKING LOTS
SIDE SLOPES 2 FT MIN
FLAT BOTTOM OVERFLOW
( ) ELEVATION
12'MW
i
,z �N DRAIN ROCK
FILTER FABRIC
OVERFLOW TO APPROVED EXISTING SUBGRADE
DISCHARGE POINT
1. Provide protection from all vehicle traffic,equipment staging, 5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of
and foot traffic in proposed infiltration areas prior to,during, impervious area,otherwise 4"min. Piping material,slopes
and after construction. and installation shall follow the Uniform Plumbing Code.
2.Dimensions: 6.Growing medium:
a.Depth of rain garden:6"minimum and 12"maximum a. In 0-2 year TOTZ,a 24"minimum with at least 50%
b.Flat bottom width:2'min. organic material
c.Side slopes of Rain Garden:3:1 maximum. b. In all other areas, 12"minimum
c. Import topsoil or amended native soil
3.Setbacks:
a.Infiltration rain gardens must be 10'from 7.Vegetation: Follow landscape plans otherwise refer to plant list in
foundations and 5'from property lines. SWMM Appendix F. Number of plantings per 100sf of facility area:
Filtration Rain Garden do not require a setback with a.100 Ground Covers, OR
an approved waterproof liner. b.80 Ground Covers,2 Large Shrubs 4 Small Shrubs
and 1 tress(deciduous or evergreen)
4.Overflow:
a.Overflows are required unless sized to fully infiltrate 8. Install washed pea gravel or river rock to transition from
the flood control design storm. inlets and splash pad to growing medium.
b.Inlet elevation must allow for 2"of freeboard,
minimum.
INFILTRATION RAIN GARDEN
TYPICAL DETAILS
0 Q
0
FLOW—SPREADER IS
REQUIRED TO EVENLY LEVEL SET GRADE
DISTRIBUTE WATER IF O
SURFACE IS UNEVEN. BOARD MAY BE o 0
REQUIRED O o CHECK DAMS OR BERMS
O 0 EVERY 10' IF FACILITY
EXCEEDS 5% SLOPE
FLOW
IMPERVIOUS AREA ° 0 0
0 0 0 0
0 0
0 0 0 0
0 0 0 0 0
° 0 00 ° COLLECTION & CONVEYANCE
o
0 0 0
° TO APPROVED DISCHARGE
0
0 8°
o° POINT.
LEVEL SPREADER
TRENCH
5FT MIN
10% MAX SLOPE
12" GROWING
MEDIUM, OR NATIVE SOIL
IF EXISTING VEGETATED
AREAS USED
1. Provide protection from all vehicle traffic,equipment staging, 6.Vegetation:The entire filter strip must have 100%coverage
as well as foot traffic for proposed infiltration areas prior to by native grasses, native wildflower blends, native ground
and during construction. covers,or any combination thereof. Follow landscape plans
otherwise refer to plant list in SWMM Appendix F. Number of
2.Dimensions: plantings per 100sf of facility area:
a.Flow line length:5'minimum. a.100 Ground Covers, OR
b.Slopes: 0.5-10% b.80 Ground Covers,4 Small Shrubs,OR
c.60 Ground Covers, 12 Small Shrubs
3.Setbacks(from beginning of facility):
a.5'from property line 7. Level Spreaders:A grade board, perforated pipe,berm or
b.10ft from buildings trench may be required to disperse the runoff evenly across
c. 50ft from wetlands,rivers,streams,and creeks the filter strip to prevent a point of discharge. The top of the
where required. level spreader must be horizontal and at an appropriate
height to provide sheet flow directly to the soil without scour.
4.Overflow:Collection from filter strip shall be specified on Grade boards can be made of any material that will withstand
plans to approved discharge point. weather and solar degradation. Trenches used as level
spreaders can be open or filled with washed crushed rock,
5.Growing medium: Unless existing vegetated areas are used pea gravel,or sand
for the filter strip,growing medium shall be used within the top
12". 8.Check dams:shall be placed according to facility design
otherwise:
a.Equal to the width of the filter
b.Every 1 O'where slope exceeds 5%.
FILTER STRIP
TYPICAL DETAILS
2° OVERFLOW
= OVERFLOW II—III= DOWNSPOUT OR OTHER
�_ I—I
_ �� ELEVATION III=III ��CONVEYANCE SYSTEM
6" IN -I I M 1 I _
12" MAX
STRUCTURAL WALLS
18" MIN FILTER SAND
FILTER FABRIC
12" MIN
DRAIN ROCK
SUB—GRADE OR'' I 1 I I I I I I f
EXISTING SOIL I II I�I I I IkI-
OVERFLOW TO APPROVED PERFORATED PIPE TO RUN
POINT OF DISCHARGE THE LENGTH OF PLANTER
24" MIN WIDTH
protection from a"vehicle traffic,equipment staging, 6.Drain rock(minimum): 12"minimum of 3/4"-2-112"washed.
and foot traffic in proposed infiltration areas prior to,during,
and after construction. 7.Separation between drain rock: Drain rock shall be separated
from sand layer and surrounding sold by a geotextile filter
2.Dimensions: fabric
a.Width:24"minimum.
b.Depth:6"minimum 8.Filter sand:
c. Slope: 0.5%or less a.18"minimum.
b.See sand specification in SWMM.
3.Setbacks(from centerline of f):
a.Infiltration sand filters must be 10'from foundations 9.Sand filter walls:
and 5'from property lines. Filtration sand filters do a.Material shall be stone, brick,concrete,wood,or
not have setbacks with an approved waterproof other durable material (no chemically treated wood).
liner. b.Filter walls built into foundation walls shall be shown
on building plans.
4.Overflow:
a.Overflows are required to an approved point of 10. Waterproof liner(where required):Shall be 30 mil PVC or
discharge. equivalent.
b.Inlet elevation must allow for 2"of freeboard,
minimum. 11. Install washed pea gravel or river rock to transition from inlet
or splash pad to growing medium.
5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of
impervious area,otherwise 4"min. Piping material,slopes
and installation shall follow the Uniform Plumbing Code.
FILTRATION SAND FILTER
TYPICAL DETAILS
2" OVERFLOW
OVERFLOW I—III—III—III- DOWNSPOUT OR OTHER
ELEVATION I I I=I I I— ��CONVEYANCE SYSTEM
6" LIN
12" MAX
STRUCTURAL WALLS
18" MIN FILTER SAND
-�I I-1 I I—I�
11 = FILTER FABRIC
SUB-GRADE OR -I II I I I I
1 II I I.
EXISTING SOIL - 11=
OVERFLOW TO APPROVED 24" MIN WIDTH-
POINT OF DISCHARGE
1. Provide protection from all vehicle traffic,equipment staging, 5.Piping: Minimum 3"pipe required for up to 1,500 sq ft of
and foot traffic in proposed infiltration areas prior to,during, impervious area, otherwise 4"min. Piping material,slopes
and after construction. and installation shall follow the Uniform Plumbing Code.
2.Dimensions:
a.Width:24"minimum 6.Filter sand:
b. Depth:6"minimum a.18"minimum.
c. Slope: 0.5%or less. b.See sand spec in SVVMM Exhibit 2-4.
3.Setbacks: 7.Sand filter walls:
a.Infiltration sand filters must be 10'from foundations a.Material shall be stone,brick,concrete,wood,or
and 5'from property lines. other durable material(no chemically treated wood).
b.Flow-through sand filters must be less than 30" in b.Concrete, brick,or stone walls shall be included on
height above surrounding area if within 5 feet of foundation plans.
property line.
8. Install washed pea gravel or river rock to transition from inlet
4.Overflow(where required): or splash pad to growing medium.
a.Overflow required for Simplified Approach.
b.Inlet elevation must allow for 2"of freeboard,
minimum.
c. Protect from debris,sand,and sediment with
strainer or grate.
INFILTRATION SAND FILTER
TYPICAL DETAILS
SILT TRAP OR OTHER
INSPECTION AccEss
■ ■
DRYWELL
DRAIN ROCK ■ ■ ■
1. All drywells are considered Class 5 injection wells and must
be registered with the Oregon Department of Environmental
Quality as Underground Injection Control(UIC)systems.
2. Provide protection from all vehicle traffic,equipment staging,
and foot traffic in proposed infiltration areas prior to,during,
and after construction.
3. Drywells shall be designed using the presumptive approach
due to the limited soil conditions in Eugene and the need to
fully infiltrate the flood control design storm. This detail is
intended to illustrate a typical drywell installation.
Installation shall conform to the drywell design provided by
the Presumptive Method.
4. Setbacks(from center of facility):
a.10'from foundations
b.5'from property lines
5. Piping: Minimum 3"pipe required for up to 1,500 sq ft of
impervious area, otherwise 4"min. Piping material,slopes
and installation shall follow the Uniform Plumbing Code.
6. Silt Traps: A silt trap or other access point is required at
finished grade for inspection and maintenance access
DRYWELL
TYPICAL DETAILS
d
4"
CD
PERFORATED p
DRAIN PIPE p
O
O
p O�J
O C
SILT BASIN OR OTHER
POINT OF ACCESS
1. All soakage trenches are considered injection wells and
must be registered with the Oregon Department of SOAKAGE TRENCH
Environmental Quality as Underground Injection Control TYPICAL CROSS SECTION
(UIC)systems.
2. Provide protection from all vehicle traffic,equipment staging,
and foot traffic in proposed infiltration areas prior to,during, FILTER FABRIC
and after construction.
3. Soakage trenches shall be designed using the presumptive 6" MIN.
approach due to the limited soil conditions in Eugene and
the need to fully infiltrate the flood control design storm.
This detail is intended to illustrate a typical soakage trench 12" MIN
installation. Installation shall conform to the soakage trench L
design provided by the Presumptive Method.
[��12" MIN PERFORATED
DRAIN PIPE
4. Setbacks(from center of facility): Y4"-2 V WASHED DRAIN
a.10'from foundations ROCK
b.5'from property lines
5. Piping: Minimum 3"pipe required for up to 1,500 sq ft of
impervious area,otherwise 4"min. Piping material,slopes
and installation shall follow the Uniform Plumbing Code.
6. Silt Traps: A silt trap or other access point is required at
finished grade for inspection and maintenance access
SOAKAGE TRENCH
TYPICAL DETAILS
APPENDIX E Exhibit A Page 66 of 133
OPERATIONS AND MAINTENANCE
This appendix presents the operation and maintenance (O&M)requirements for stormwater
management facilities designed and installed in the City of Springfield pursuant to SDC 4.3.110.
INTRODUCTION
Notice of Operations and Maintenance Agreement— (NOMA)
The NOMA must be in a form approved by the City Attorney and must identify the property as
having a stormwater management facility and the responsible parry for future operations and
maintenance. The NOMA must be completed and recorded at Lane County Deeds and Records.
Signatures on the NOMA shall be notarized.
The intent of the NOMA is to ensure that the facility will be identified to future property owners and
that the facility will be maintained according to the Springfield Development Code, Springfield
Municipal Code,the O&M Agreement, and the O&M Plan for the site.
Operations and Maintenance Agreement—(O&M Agreement)
The O&M Agreement must be on a form approved by the City Attorney and must identify the
property as having a stormwater management facility; the owner's name, address, email, and phone
number; the site address; financially responsible parry for ongoing operation and maintenance; and
parties responsible for inspecting and maintaining the facility.
The O&M Agreement does not need to be recorded. The intent of the Agreement is to ensure that the
facility will be maintained for functionality, aesthetics, and will identify accountability. The
stormwater site plan attached to the Agreement will help identify to the owners and inspectors the
location and the functions of the stormwater facilities, and the Facility Specific O&M Plan will
identify the routine maintenance procedures and scheduling.
Facility Specific Operations and Maintenance Plan— (&M Plan)
This appendix provides pre-approved_Facility Specific Operations and Maintenance Plans (O&M
Plans) for various types of stormwater quality facilities. Stormwater facilities that are not included in
this appendix(i.e. a manufactured stormwater treatment technology), are required to submit an O&M
Plan that meets the manufacturer's requirements and facility specific operations and maintenance
activities consistent with ongoing function of the stormwater facility(ies).
The O&M Plan strategies in this appendix apply to all stormwater management facilities and related
facility components identified in SDC 4.3.110. Stormwater destination facilities are required to be
operated and maintained in working condition for the life of the facility.
Private Facilities:
Record a copy of the NOMA with Lane County Deeds and Records. Submit with the final site plan, a
recorded copy of the NOMA, the O&M Agreement, and the Facility Specific Operations and
Maintenance Plan (O&M Plan) for each type of stormwater management facility permitted on the site.
The operations and maintenance activities listed on the O&M Plan documents,which will be on file
with the City Engineer,may later be revised with City Engineer approval.
Public Facilities:
Appendix E—Operations and Maintenance
Stormwater Post-construction Requirements Update Ordinance No. 6464
Submit a copy of a Facility Specific O&M Plan with the Public Improveme��09 FtNgjP�tofC1atbty
recording of this plan is not necessary.
OPERATIONS AND MAINTENANCE PLAN SUBMITTALS
Privately Maintained Facilities
The O&MPlan for a privately maintained facility shall include the following components for each
development site. A complete Plan must be submitted and approved as provided in SDC 4.3.110.
1. A recorded copy of the Notice of Operation and Maintenance Agreement(NOMA)
2. Operations and Maintenance Agreement(O&M Agreement)
3. Stormwater Management Site Plan (as approved under the Development Agreement)
4. Landscape Plan
5. Stormwater Management Facility Inspection and Maintenance Log
6. Facility-Specific Operations and Maintenance Plan(s) (O&M Plan(s))
Detailed submission requirements for the above items are found below.
1.) Notice of Operations and Maintenance Agreement—(NOMA): The NOMA identifies the
property as having a stormwater management facility and identifies the responsible party for
future operations and maintenance. The Notice must be completed and recorded at Lane County
Deeds and Records. Signatures on the Notice shall be notarized. The NOMA maybe submitted
in person or mailed, along with payment of the applicable fees,to the County Recorder's Office.
Lane County Deeds and Records, 125 E 81 Avenue, Eugene, OR 97401.
hiips://www.lanecouniy.org/govemment/county_departments/county_administration/operations/c
ount_y_clerk/real property_recording/document recording requirements
The property description on the NOMA must be a full legal description of the property and may
not be a tax lot number. Legal descriptions may be obtained from the county assessor's office. The
NOMA shall be printed on legal-sized(8 %x 14)paper to facilitate the recording process. If
printed on smaller paper, additional recording fees may apply.
2.) Operations and Maintenance Agreement—(O&M Agreement): The completed Agreement
must identify the owner's name, address, and phone number,the site address, financial method
used to cover future operation and maintenance, and parties responsible for inspecting and
maintaining the facility. The O&M Agreement does not need to be recorded.
3.) Stormwater Management Site Plan: A copy of the Stormwater Management Site Plan shall
be attached to the O&M Agreement. The Plan must show the location of the facility(ies) on the
site,the sources of runoff entering the facility, and the ultimate stormwater destination.
4.) Landscape Plan: A Landscape Plan (if separate from the Stormwater Management Site Plan)
shall be attached to the O&M Agreement. The Plan must show the location, density,plant size,
quantity, and species by scientific and common name.
Appendix E—Operations and Maintenance
Stormwater Post-construction Requirements Update Ordinance No. 6464
Exhibit A Page 68 of 133
5.) Stormwater Management Facility Inspection and Maintenance Log., Stormwater
Management Facility Inspection and Maintenance Logs must be kept on file by the facility
owner(s). Logs should note all inspection dates, the facility components that were inspected, and
any maintenance or repairs made. The Facility-Specific O&M Plans can serve as a checklist for
what should be included in the Log (e.g. the facility elements that need to be inspected, frequency
of inspection, conditions that indicate maintenance is needed, etc.). Logs must include the
information listed in the form included in this appendix. Logs must be retained on site for a
minimum of two years.
6.) Facility Specific Operations and Maintenance Plans—(O&M Plan): O&M Plans provided
in this packet identify the specific operations and maintenance activities that are required for each
of the approved stormwater management facilities listed in Appendix D Stormwater Facility
Details. The appropriate Plan must be attached to the O&M Agreement and submitted as part of
the application process. Applicants may either select and use the pre-approved Facility Specific
O&M Plans provided in this packet or prepare a Facility Specific O&M Plan that incorporates the
specific activities that corresponds with their chosen type of stormwater facilities through a Type
II review process. The Facility Specific O&M Plans do not have to be recorded. This allows the
future stormwater management facility owner to submit operations and maintenance activity
revisions to the City without the need to re-record the O&M Plans with the County.
The facility specific operations and maintenance activities for private facilities may be modified
any time after permit issuance subject to mutual agreement by the City and owner,in writing.
Modifying the operations and maintenance activities is optional, and is intended to give the owner
an opportunity to adjust maintenance needs according to site-specific history and conditions.
Modifications may require the owner to apply for concurrent modification of a prior land use
approval. Proposed modifications to the O&M Plan must be submitted, along with an updated
O&M Agreement,to the City for review and approval.
7.) Operations and Maintenance Plans for Proprietary Facilities:Proprietary O&M Plans for
approved proprietary facilities must describe the inspection, cleaning, and operation and
maintenance criteria for the facility and provide manufacturer's recommended maintenance if
applicable.
Appendix E—Operations and Maintenance
Stormwater Post-construction Requirements Update Ordinance No. 6464
Exhibit A Page 69 of 133
Stormwater Management Facility
Inspection & Maintenance Log
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 70 of 133
STORMWATER MANAGEMENT FACILITY
INSPECTION AND MAINTENANCE LOG
Property Address:
-Inspection Date:
Inspection Time:
-Inspected By:
Approximate Date/Time of Last Rainfall:
Type of Stormwater Management Facility:
Location of Facility on Site (in relation to buildings or other permanent structures):
Water levels and observations (ponded water (indicating poor soil permeability), oil sheen,
smell, turbidity, etc.):
Sediment accumulation and/or areas of erosion? Record sediment removal/erosion repair:
Condition of vegetation? Record survival rates, invasive species present,number of dead plants,
etc. Record any replacement of plants and type of management(mowing,weeding, etc.):
Condition of physical properties such as inlets, outlets, piping,fences, irrigation facilities, and
side slopes? Record damaged items and replacement activities:
Presence of litter? Presence of insects or damage from animals? Record removal activities:
Identify safety hazards present. Record resolution activities:
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 71 of 133
Facility Specific
Operations &Maintenance Plans
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 72 of 133
FACILITY SPECIFIC OPERATIONS
AND
MAINTENANCE PLANS
Eco-Roofs
Contained Planters
Permeable Pavement
Swales (Vegetated, Grassy and Street)
Level Spreaders
Vegetated Filter Strips
Stormwater Planters
Rain Gardens
Sand Filters
Soakage Trenches
Wet,Extended Wet,-and Dry Ponds
Constructed Treatment Wetlands
Underground Detention Tanks,Vaults and Pipes
Drywells
Spill Control Manholes
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 73 of 133
Eco-Roofs
Operations and Maintenance Plan
Eco-Roofs are lightweight vegetated roof systems used in place of conventional roofs that retain and filter
stormwater and provide aesthetic and energy conservation benefits.All facility components,including
soil substrate or growth medium,vegetation,drains, irrigation systems(if applicable),membranes,and
roof structure shall be inspected for proper operations,integrity of the waterproofing, and structural
stability throughout the life of the eco-roof.All elements shall be inspected once a month from April
through September. The facility owner must keep a log,recording all inspection dates,observations, and
maintenance activities.The following items shall be inspected and maintained as stated:
Soil Substrate/Growing Medium shall be inspected for evidence of erosion from wind or water.
If erosion channels are evident,they shall be stabilized with additional soil substrate/growth medium and
covered with additional lants.
Structural Components shall be operated and maintained in accordance with manufacturer's
requirements. Drain inlets shall be kept unrestricted.
• Inlet/outlet pipe shall be cleared when soil substrate,vegetation,debris or other materials clog the
drains. Sources of sediment and debris shall be identified and corrected.
• Determine if drain pipe is in good condition and correct as needed.
Debris and Litter shall be removed to prevent clogging of drains and interference with plant growth.
Vegetation shall be maintained to provide 90%plant cover.
• During the Establishment Period,plants shall be replaced once per month as needed. During the long-
term period, dead plants shall generally be replaced once per year in the fall months.
• Fallen leaves and debris from deciduous plant foliage shall be removed if build up occurs.
• Nuisance and prohibited vegetation shall be removed when discovered.
• Dead vegetation shall be removed and replaced with new plants.
• Weeding shall be manual with no herbicides or pesticides used. Weeds shall be removed regularly
and not allowed to accumulate.
• Fertilization is not necessary and fertilizers shall not be applied.
• During drought conditions,mulch or shade cloth may be applied to prevent excess solar damage and
water loss.
• Mowing of grasses shall occur as needed. Clippings shall be removed if build up occurs.
Irrigation can be accomplished either through hand watering or automatic sprinkler systems. If automatic
sprinklers are used,manufacturers' instructions for operations and maintenance shall be followed.
• During the Establishment Period(1-3 years),water sufficient to assure plant establishment and not to
exceed I/4 inch of water once every 3 days shall be applied.
• During the long-term period(3+years),water sufficient to maintain plant cover and not to exceed 1/4
inch of water once every 14 days shall be applied.
Spill Prevention measures from mechanical systems located on roofs shall be exercised when handling
substances that can contaminate stormwater.
• Releases of pollutants shall be corrected as soon as identified.
• The presence of a green/eco roof does not waive requirements for containment of mechanical
systems.
Training and/or written guidance information for operating and maintaining rooftop gardens shall be
provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access and Safety to the eco-roof shall be safe and efficient.
• Egress and ingress routes shall be maintained to design standards. Walkways shall be clear of
obstructions and maintained to design standards.
Aesthetics of the rooftop garden shall be maintained as an asset to the property owner and community.
• Evidence of damage or vandalism shall be repaired and accumulation of trash or debris shall be
removed upon discovery.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 74 of 133
Insects shall not be harbored on the eco-roof.
• Standing water creating an environment for development of insect larvae shall be eliminated by
manual means. Chemicalsprays shall not be used.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 75 of 133
Contained Planters
Operations and Maintenance Plan
Contained planters are designed to intercept rainfall that would normally fall on impervious surfaces. In
this respect, contained planters convert impervious surfaces to pervious surfaces, decreasing the amount
of stormwater runoff from a site. Water should drain through the planter within 3-4 hours after a storm
event.All facility components and vegetation shall be inspected for proper operations and structural
stability. These inspections shall occur,at a minimum,quarterly for the first 2 years from the date of
installation and 2 times per year thereafter. The facility owner must keep a log,recording all inspection
dates,observations, and maintenance activities.The following items shall be inspected and maintained as
stated:
Filter Media consisting of sand or topsoil shall allow stormwater to percolate uniformly through the
planter.
• Planter shall be excavated and cleaned,and gravel or soil shall be replaced to correct low infiltration
rates.
• Holes that are not consistent with the design and allow water to flow directly through the planter to
the ground shall be plugged.
• Litter and debris shall be removed routine) (e.g.,no less than quarterly)and upon discovery
Planter shall contain filter media and vegetation.
• Structural deficiencies in the planter including rot,cracks, and failure shall be repaired.
Planter Reservoir receives and detains storm water prior to infiltration. If water does not drain from
reservoir within 3-4 hours of storm event, sources of clogging shall be identified and corrected.Topsoil
may need to be amended with sand or replaced all together.
Vegetation shall be healthy and dense enough to provide filtering while protecting underlying soils from
erosion.
• Mulch shall be replenished at least annually.
• Planter vegetation shall be irrigated to ensure survival.
• Vegetation or trees that limit access or interfere with planter operation shall be pruned or removed.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed.
• Nuisance and prohibited vegetation shall be removed when discovered. Invasive vegetation
contributing up to 25%of vegetation of all species(measured in a 10 x 10 foot plot)shall be removed
and replaced.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when planter
function is impaired. Vegetation shall be replaced within a specific timeframe,e.g.,3 months, or
immediately if required to maintain cover density and control erosion where soils are exposed.
Training and/or written guidance information for operating and maintaining planters shall be provided
to all property owners and tenants.A copy of the O&M Plan shall be provided to all property owners and
tenants.
Access to the stormwater planter shall be safe and efficient. Egress and ingress routes shall be maintained
to design standards. Roadways shall be maintained to accommodate size and weight of vehicles,if
applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the planter shall be removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored at the stormwater planter. Pest control measures shall be
taken when insects/rodents are found to be present.
• Standing water creating an environment for development of insect larvae shall be eliminated.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first nonchemical methods and secondly,only those chemical methods
specifically approved by the City's inspector. Acceptable methods include but are not limited to the
following:
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 76 of 133
I. Installation of predacious bird or bat nesting boxes.
ii. Alterations of water levels approximately every 4 days in order to disrupt mosquito larval
cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or
other approved larvicides.These materials may only be used with City inspector approval if
evidence can be provided that these materials will not migrate off-site or enter the public
stormwater system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the stormwater planter shall be filled and
compacted.
Debris and Litter shall be removed to maintain soil health and to prevent interference with plant growth.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 77 of 133
Permeable Pavement
Operations and Maintenance Plan
Permeable Pavement is a porous pavement surface with an underlying stone reservoir that temporarily
stores surface runoff before infiltrating into the subsoil or being collected in underlying drain pipes and
being discharged off-site.There are many types of permeable pavement including plastic rings planted
with grass, stone or concrete blocks with pore spaces backfilled with gravel or sand,porous asphalt,and
porous concrete.Permeable pavement accepts only precipitation,not stormwater runoff. All facility
components,vegetation, and source controls shall be inspected for proper operations and structural
stability,at a minimum,quarterly for the first 2 years from the date of installation,2 times per year
thereafter,and within 48 hours after each major storm event. The facility owner must keep a log,
recording all inspection dates,observations, and maintenance activities.The following items shall be
inspected and maintained as stated:
Surface: In most permeable pavement design,the pavement itself acts as pretreatment to the stone
reservoir below. The surface shall be kept clean and free of leaves,debris, and sediment. The surface shall
not be overlaid with an impermeable paving surface.
• Regular sweeping shall be implemented for porous asphalt or concrete systems.Vacuum sweeping is
referred and can greatly prolongthe effective life of the pavement.
Overflows or Emergency Spillways are used in the event that the facility's infiltration capacity is
exceeded.Overflow devices shall be inspected for obstructions or debris,which shall be removed upon
discovery. Overflow or emergency spillways shall be capable of transporting high flows of stormwater to
an approved stormwater receiving system.
• Sources of erosion damage shall be identified and controlled when native soil is exposed near the
overflow structure.
Vegetation (where applicable) shall be healthy and dense enough to provide filtering while protecting
underlying soils from erosion.Vegetation,such as trees and shrubs,should not be located in or around the
permeable pavement because roots from trees can penetrate the pavement, and leaves from deciduous
trees and shrubs can increase the risk of clogging the surface.
• Vegetation and large shrubs/trees that limit access or interfere with porous pavement operation shall
be pruned.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed.
• Poisonous,nuisance, dead or odor producing vegetation shall be removed immediately.
• Grass shall be mowed to less than four inches and grass clippings shall be bagged and removed.
• Irrigation shall be provided as needed.
Source Control measures prevent pollutants from mixing with stormwater.Typical non-structural control
measures include raking and removing leaves, street sweeping,vacuum sweeping,limited and controlled
application of pesticides and fertilizers,and other good housekeeping ractices.
Spill Prevention measures shall be exercised when handling substances that can contaminate stormwater.
A spill prevention plan shall be implemented at all non-residential sites and in areas where there is
likelihood of spills from hazardous materials.However,virtually all sites,including residential and
commercial,present potential danger from spills.All homes contain a wide variety of toxic materials
including gasoline for lawn mowers, antifreeze for cars, solvents,pesticides, and cleaning aids that can
adversely affect stormwater if spilled. It is important to exercise caution when handling substances that
can contaminate stormwater.Releases of pollutants shall be corrected as soon as identified. In addition,
long term exposure to low levels of petroleum products, such as that form a leaky vehicle,can severely
degrade the pavement.
Training and/or written guidance information for operating and maintaining permeable pavement shall
be provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the permeable pavement shall be safe and efficient.Egress and ingress routes shall be
maintained to design standards. Roadways shall be maintained to accommodate size and weight of
vehicles,if applicable. Obstacles preventing maintenance personnel and/or equipment access to the
porous pavement shall be removed. Gravel or ground cover shall be added if erosion occurs, e.g.,due to
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 78 of 133
vehicular or pedestrian traffic.
Debris and Litter shall be removed to prevent clogging.
Insects and Rodents shall not be harbored at the permeable pavement. Pest control measures shall be
taken when insects/rodents are found to be present.
• Standing water creating an environment for development of insect larvae shall be eliminated.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
I. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito
larval development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful, contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or
other approved larvicides. These materials may only be used with City inspector approval if
evidence can be provided that these materials will not migrate off-site or enter the public
stormwater system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the permeable pavement shall be filled and compacted.
If used at this site, the following will be applicable:
Signage may serve to educate people about the importance or function of the site's stormwater protection
measures.It may also discourage behaviors that adversely affect stormwater protection measures. For
example,if debris is a problem, a sign reminding people not to litter may partially solve the problem.
Broken or defaced signs shall be replaced/repaired.
Placing of permeable pavement on site:
Permeable pavement should not be placed in any area where there is high likelihood of spills or
contamination such as vehicle fueling areas,washing areas,loading docks,trash enclosures or material
handling areas.Permeable pavement is not well suited to high traffic areas or areas where heavy vehicles
will frequently travel. Such areas include parking lot lanes,entrance lanes and any areas subject to vehicle
braking and turning movements. Parking lot stalls,emergency access areas and infrequently used areas
are typically suitable for permeable pavement treatment.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 79 of 133
Swales(Vegetated, Grassy and Street)
Operations and Maintenance Plan
Swales are vegetated or grassed open channels that trap pollutants by filtering and slowing flows,
allowing particles to settle out.The Swale should drain within 48 hours of a storm event. All facility
components,vegetation, and source controls shall be inspected for proper operations and structural
stability,at a minimum,quarterly for the first 2 years from the date of installation,2 times per year
thereafter,and within 48 hours after each major storm event. The facility owner must keep a log,
recording all inspection dates,observations, and maintenance activities. The following items shall be
inspected and maintained as stated:
Swale Inlet(such as curb cuts or pipes)shall maintain a calm flow of water entering the Swale.
• Source of erosion shall be identified and controlled when native soil is exposed or erosion channels
are forming.
• Sediment accumulation shall be hand-removed with minimum damage to vegetation using proper
erosion control measures. Sediment shall be removed if it is more than 3" thick or so thick as to
damage or kill vegetation.
• Inlet shall be cleared when conveyance capacity is plugged. Sources of sediment and debris shall be
identified and corrected.
• Rocks lash pads,spreaders and dissipaters shall be replenished to prevent erosion.
Side Slopes shall be maintained to prevent erosion that introduces sediment into the Swale.
• Slopes shall be stabilized and planted using appropriate erosion control measures when native soil is
exposed or erosion channels are forming.
Swale Media shall allow stormwater to percolate uniformly through the landscape Swale.If the swale
does not drain within 48 hours,it shall be tilled and replanted according to design specifications.
• Swale area shall be protected during construction from compaction.
• Annual or semi-annual tilling shall be implemented if compaction or clogging continues.
• Debris in quantities that inhibit operation shall be removed routinely(e.g.,no less than quarterly), or
upon discovery.
Swale Outlet shall maintain sheet flow of water exiting Swale unless a collection drain is used. Source of
erosion damage shall be identified and controlled when native soil is exposed or erosion channels are
forming.
• Outlets such as drains and overland flow paths shall be cleared when 50% of the conveyance capacity
is plugged.
• Outlet structures shall be cleaned of sediment and debris at least I time per year or when the level is
at 50%of the conveyance capacity.
• Sources of sediment and debris shall be identified and corrected.
Vegetation shall be healthy and dense enough (at least 90%cover)to provide filtering while protecting
underlying soils from erosion.Mulch shall be replenished as needed to ensure survival of vegetation.
• Vegetation,large shrubs or trees that interfere with landscape Swale operation shall be pruned.
• Fallen leaves and debris from deciduous plant foliage shall be removed if build up is damaging
vegetation.
• Grassy swales shall be mowed to keep grass 4"to 9"in height. Clippings shall be removed when
possible,to remove pollutants absorbed in grasses,or when build up is damaging vegetation.
• Nuisance and prohibited vegetation(such as blackberries and English Ivy) shall be removed when
discovered. Invasive vegetation contributing up to 25%of vegetation of all species shall be removed
and replaced.
• Dead vegetation and woody material shall be removed to maintain less than 10%of area coverage or
when swale function is impaired. Vegetation shall be replaced within 3 months,or immediately if
required to maintain cover density and control erosion where soils are exposed.
Debris and Litter shall be removed to ensure stormwater conveyance and to prevent clogging of inlet
and outlet drains and interference with plant growth.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 80 of 133
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining swales shall be provided
to all property owners and tenants.A copy of the O&M Plan shall be provided to all property owners and
tenants.
Access to the Swale shall be safe and efficient. Egress and ingress routes shall be maintained to design
standards. Roadways shall be maintained to accommodate size and weight of vehicles,if applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the Swale shall be removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the Swale. Pest control measures shall be taken when
insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system.Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the Swale shall be filled.
If used at this site, the following will be applicable:
Check Dams,flow spreaders and dissipaters shall control and distribute flow.
• Causes for altered water flow or short circuits shall be identified,and obstructions cleared upon
discovery.
• Causes for channelization shall be identified and repaired.
• Systems shall remain free of sediment build up and debris.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 81 of 133
Level Spreaders
Operations and Maintenance Plan
Level Spreaders are used to spread and disperse a concentrated flow thinly over a vegetated or forested
riparian buffer or filter strip. Stormwater enters the spreader as a concentrated flow and discharges as
sheet flow across a buffer area.All facility components and the vegetated buffer shall be inspected for
proper operations and structural stability. These inspections shall occur,at a minimum,quarterly for the
first 2 years from the date of installation,2 times per year thereafter, and within 48 hours after each major
storm event.The facility owner must keep a log,recording all inspection dates,observations, and
maintenance activities.The following items shall be inspected and maintained as stated:
Level Spreader shall allow runoff to enter the vegetative filter as predominantly sheet flow.
• Source of erosion damage shall be identified and controlled when native soil is exposed or erosion
channels are forming.
• Sediment build-up near or exceeding 2"in depth shall be removed.
Inlet shall assure unrestricted stormwater flow to the level spreader.
• Sources of erosion shall be identified and controlled when native soil is exposed or erosion channels
are present.
• Sediment accumulation shall be hand-removed with minimum damage to vegetation using proper
erosion control measures. Sediment shall be removed if it is more than 3 inches thick or so thick as to
damage or kill vegetation.
• Inlet shall be cleared when conveyance capacity is plugged.
• Rocks lash pads and dissipaters shall be replenished to prevent erosion.
Spreader lip shall allow water to exit the level spreader as sheet flow.
• Sources of erosion damage shall be identified and controlled when native soil is exposed or erosion
channels are deeper than 2 inches.
• Outlet shall be cleared when 50%of the conveyance capacity is plugged. Sources of sediment and
debris shall be identified and corrected.
Vegetated buffer shall be healthy and dense enough (at least 90%cover)to provide filtering while
protecting underlying soils from erosion.
• Nuisance and prohibited vegetation(such as blackberries and English Ivy) shall be removed when
discovered. Invasive vegetation contributing up to 25%of vegetation of all species shall be removed
and replaced.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when vegetation
function is impaired. Vegetation shall be replaced immediately to control erosion where soils are
exposed and within 3 months to maintain cover density.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining level spreaders shall be
provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the level spreaders shall be safe and efficient.Egress and ingress routes shall be maintained to
design standards. Obstacles preventing maintenance personnel and/or equipment access to the facility
shall be removed.
Insects and Rodents shall not be harbored in the level spreader. Pest control measures shall be taken
when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 82 of 133
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the levels reader shall be filled.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 83 of 133
Vegetated Filter Strips
Operations and Maintenance Plan
Vegetated Filter Strips are gently sloped vegetated areas that stormwater runoff is directed to flow and
filter through. Stormwater enters the filter as sheet flow from an impervious surface or is converted to
sheet flow using a flow spreader.Flow control is achieved using the relatively large surface area and
check dams.Pollutants are removed through infiltration and sedimentation.The vegetative filter should
drain within 48 hours of storm event.All facility components and vegetation shall be inspected for proper
operations and structural stability.These inspections shall occur,at a minimum,quarterly for the first 2
years from the date of installation,2 times per year thereafter, and within 48 hours after each major storm
event.The facility owner must keep a log,recording all inspection dates,observations,and maintenance
activities.The following items shall be inspected and maintained as stated:
Flow Spreader shall allow runoff to enter the vegetative filter as predominantly sheet flow.
• Source of erosion damage shall be identified and controlled when native soil is exposed or erosion
channels are forming.
• Sediment build-up near or exceeding 2 inch in depth shall be removed.
Filter Inlet shall assure unrestricted stormwater flow to the vegetative filter.
• Sources of erosion shall be identified and controlled when native soil is exposed or erosion channels
are present.
• Sediment accumulation shall be hand-removed with minimum damage to vegetation using proper
erosion control measures. ediment shall be removed if it is more than 2 inches thick or so thick as to
damage or kill vegetation.
• Inlet shall be cleared when conveyance capacity is plugged.
• Rocks lash pads shall be replenished to prevent erosion.
Filter Media shall allow stormwater to percolate uniformly through the vegetative filter.
• If the vegetative filter does not drain within 48 hours, it shall be re-graded and replanted according to
design specifications. Established trees shall not be removed or harmed in this process.
• Debris in quantities more than 2 inch deep or sufficient to inhibit operation shall be removed
routinely (e.g.,no less than quarterly),or upon discovery.
Check Dams and Dissipaters shall direct and control flow.
• Causes for altered water flow and channelization shall be identified,and obstructions cleared upon
discovery.
• Cracks,rot,and structural damage shall be repaired.
Filter Outlet shall allow water to exit the vegetative filter as sheet flow,unless a collection drainpipe is
used.
• Sources of erosion damage shall be identified and controlled when native soil is exposed or erosion
channels are deeper than 2 inches.
• Outlet shall be cleared when 50%of the conveyance capacity is plugged. Sources of sediment and
debris shall be identified and corrected.
Vegetation shall be healthy and dense enough (at least 90%cover)to provide filtering while protecting
underlying soils from erosion.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed if build up is
damaging vegetation.
• Nuisance and prohibited vegetation(such as blackberries and English Ivy) shall be removed when
discovered. Invasive vegetation contributing up to 25%of vegetation of all species shall be removed
and replaced.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when vegetative
filter function is impaired.Vegetation shall be replaced immediately to control erosion where soils are
exposed and within 3 months to maintain cover density.
Debris and Litter shall be removed to ensure stormwater conveyance and to prevent clogging of inlet
and outlet drains and interference with plant growth.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 84 of 133
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining vegetated filters shall be
provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the vegetative filter shall be safe and efficient.Egress and ingress routes shall be maintained to
design standards. Obstacles preventing maintenance personnel and/or equipment access to the facility
shall be removed.Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or
pedestrian traffic.
Insects and Rodents shall not be harbored in the vegetated filter. Pest control measures shall be taken
when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system.Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the vegetated filter shall be filled.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 85 of 133
Stormwater Planters
Operations and Maintenance Plan
Stormwater Planters are designed to allow runoff to filter through layers of topsoil(thus capturing
pollutants)and then either infiltrate into the native soils(infiltration planter)or be collected in a pipe to be
discharged off-site (flow-through planter). The planter is sized to accept runoff and temporarily store the
water in a reservoir on top of the soil. The flow-through planter is designed with an impervious bottom or
is placed on an impervious surface. Water should drain through the planter within 3-4 hours after a storm
event.All facility components and vegetation shall be inspected for proper operations and structural
stability. These inspections shall occur,at a minimum,quarterly for the first 2 years from the date of
installation, 2 times per year thereafter, and within 48 hours after each major storm event. The facility
owner must keep a log,recording all inspection dates,observations,and maintenance activities. The
following items shall be inspected and maintained as stated:
Downspout from rooftop or sheet flow from paving allows unimpeded stormwater flow to the planter.
• Debris shall be removed routinely(e.g.,no less than every 6 months)and upon discovery.
• Damaged pipe shall be repaired upon discovery.
Splash Blocks prevent splashing against adjacent structures and convey water without disrupting media.
• Any deficiencies in structure such as cracking,rotting, and failure shall be repaired.
Planter Reservoir receives and detains storm water prior to infiltration. Water should drain from
reservoir within 3-4 hours of storm event.
• Sources of clogging shall be identified and corrected to prevent short circuiting.
• Topsoil may need to be amended with sand or replaced all together to achieve a satisfactory
infiltration rate.
Filter Media consisting of sand,gravel and topsoil shall allow stormwater to percolate uniformly through
the planter. The planter shall be excavated and cleaned, and gravel or soil shall be replaced to correct low
infiltration rates.
• Holes that are not consistent with the design and allow water to flow directly through the planter to
the ground shall be plugged.
• Sediment accumulation shall be hand removed with minimum damage to vegetation using proper
erosion control measures. Sediment shall be removed if it is more than 4 inches thick or so thick as to
damage or kill vegetation.
• Litter and debris shall be removed routine) (e.g.,no less than quarterly) and upon discovery.
Planter shall contain filter media and vegetation.
• Structural deficiencies in the planter including rot,cracks, and failure shall be repaired.
Overflow Pipe safely conveys flow exceeding reservoir capacity to an approved stormwater receiving
system.
• Overflow pipe shall be cleared of sediment and debris when 50%of the conveyance capacity is
plugged.
• Damaged pipe shall be repaired or replaced upon discovery.
Vegetation shall be healthy and dense enough (at least 90%cover)to provide filtering while protecting
underlying soils from erosion.
• Mulch shall be replenished at least annually.
• Vegetation,large shrubs or trees that limit access or interfere with planter operation shall be pruned or
removed.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed if build up is
damaging vegetation.
• Nuisance or prohibited vegetation shall be removed when discovered. Invasive vegetation
contributing up to 25%of vegetation of all species shall be removed and replaced.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when planter
function is impaired.Vegetation shall be replaced within a specific timeframe,e.g.,3 months, or
immediately if required to maintain cover density and control erosion where soils are exposed.
Debris and Litter shall be removed to ensure stormwater infiltration and to prevent clogging of overflow
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 86 of 133
drains and interference with plant growth.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining stormwater planters shall
be provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the stormwater planter shall be safe and efficient.Egress and ingress routes shall be maintained
to design standards. Roadways shall be maintained to accommodate size and weight of vehicles,if
applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the stormwater planter shall
be removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the stormwater planter.Pest control measures shall be taken
when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
I. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the stormwater planter shall be filled and compacted.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 87 of 133
Rain Gardens
Operations and Maintenance Plan
A vegetated Infiltration Basin or rain garden is a vegetated depression created by excavation,berms,
or small dams to provide for short-term ponding of surface water until it percolates into the soil.The
basin shall infiltrate stormwater within 24 hours. All facility components and vegetation shall be
inspected for proper operations and structural stability, at a minimum,quarterly for the first 2 years from
the date of installation,2 times per year thereafter, and within 48 hours after each major storm event. The
facility owner must keep a log,recording all inspection dates,observations,and maintenance activities.
The following items shall be inspected and maintained as stated:
Basin Inlet shall assure unrestricted stormwater flow to the vegetated basin.
• Sources of erosion shall be identified and controlled when native soil is exposed or erosion channels
are present.
• Inlet shall be cleared when conveyance capacity is plugged.
• Rocks lash pads shall be replenished to prevent erosion.
Embankment, Dikes,Berms and Side Slopes retain water in the infiltration basin.
• Structural deficiencies shall be corrected upon discovery:
o Slopes shall be stabilized using appropriate erosion control measures when soil is exposed/flow
channels are forming.
o Sources of erosion damage shall be identified and controlled.
Overflow or Emergency Spillway conveys flow exceeding reservoir capacity to an approved stormwater
receiving system.
• Overflow shall be cleared when 25%of the conveyance capacity is plugged.
• Sources of erosion damage shall be identified and controlled when soil is exposed.
• Rocks or other armament shall be replaced when only one layer of rock exists.
Filter Media shall allow stormwater to percolate uniformly through the infiltration basin.If water
remains 36-48 hours after storm,sources of possible clogging shall be identified and corrected.
• Basin shall be raked and, if necessary,soil shall be excavated, and cleaned or replaced.
• Infiltration area shall be protected from compaction during construction.
Sediment/Basin Debris Management shall prevent loss of infiltration basin volume caused by
sedimentation. Gauges located at the opposite ends of the basin shall be maintained to monitor
sedimentation.
• Sediment and debris exceeding 3 inch in depth shall be removed every 2-5 years or sooner if
performance is affected.
Debris and Litter shall be removed to ensure stormwater infiltration and to prevent clogging of overflow
drains and interference with plant growth.
• Restricted sources of sediment and debris, such as discarded lawn clippings, shall be identified and
prevented.
Vegetation shall be healthy and dense enough(at least 90%cover)to provide filtering while protecting
underlying soils from erosion.
• Mulch shall be replenished as needed to ensure healthy plant growth
• Vegetation,large shrubs or trees that limit access or interfere with basin operation shall be pruned or
removed.
• Grass shall be mowed to 4"-9"high and grass clippings shall be removed no less than 2 times per
year.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed if build up is
damaging vegetation.
• Nuisance or prohibited vegetation (such as blackberries or English Ivy)shall be removed when
discovered. Invasive vegetation contributing up to 25%of vegetation of all species shall be removed.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when infiltration
basin function is impaired.Vegetation shall be replaced within 3 months, or immediately if required
to control erosion.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 88 of 133
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining vegetated infiltration
basins shall be provided to all property owners and tenants.A copy of the O&M Plan shall be provided to
all property owners and tenants.
Access to the infiltration basin shall be safe and efficient.Egress and ingress routes shall be maintained to
design standards. Roadways shall be maintained to accommodate size and weight of vehicles,if
applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the infiltration basin shall be
removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the infiltration basin.Pest control measures shall be taken
when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
I. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the infiltration basin shall be filled.
If used at this site, the following will be applicable:
Fences shall be maintained to preserve their functionality and appearance.
• Collapsed fences shall be restored to an upright position.
• Jagged edges and damaged fences shall be repaired or replaced.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 89 of 133
Sand Filters
Operations and Maintenance Plan
Sand filters consist of a layer of sand in a structural box used to trap pollutants. The water filters through
the sand and then flows into the surrounding soils or an underdrain system that conveys the filtered
stormwater to a discharge point.All facility components,vegetation, and source controls shall be
inspected for proper operations and structural stability. These inspections shall occur,at a minimum,
quarterly for the first 2 years from the date of installation,and 2 times per year thereafter,and within 48
hours after each major storm event. The facility owner must keep a log,recording all inspection dates,
observations,and maintenance activities. The following items shall be inspected and maintained as
stated:
Filter Inlet shall allow water to uniformly enter the sand filter as calm flow, in a manner that prevents
erosion.
• Inlet shall be cleared of sediment and debris when 40%of the conveyance capacity is plugged.
• Source of erosion damage shall be identified and controlled when native soil is exposed or erosion
channels are forming.
• Sediment accumulation shall be hand-removed with minimum damage to vegetation using proper
erosion control measures. Sediment shall be removed if it is more than 4 inches thick or so thick as to
damage or kill vegetation.
• Rocks lash pads shall be replenished to prevent erosion.
Reservoir receives and detains stormwater prior to infiltration. If water does not drain within 2-3 hours of
storm event,sources of clogging shall be identified and correction action taken.
• Debris in quantities more than I cu ft or sufficient to inhibit operation shall be removed routinely
(e.g.,no less than quarterly), or upon discovery.
• Structural deficiencies in the sand filter box including rot, cracks, and failure shall be repaired upon
discovery.
Filter Media shall allow to stormwater to infiltrate uniformly through the sand filter. If water remains 36-
48 hours after storm, sources of possible clogging shall be identified and corrected.
• Sand filter shall be raked and if necessary,the sand/gravel shall be excavated, and cleaned or
replaced.
• Sources of restricted sediment or debris(such as discarded lawn clippings)shall be identified and
prevented.
• Debris in quantities sufficient to inhibit operation shall be removed no less than quarterly, or upon
discovery.
• Holes that are not consistent with the design structure and allow water to flow directly through the
sand filter to the ground shall be filled.
• The infiltration area shall be protected from compaction during construction.
Underdrain Piping(where applicable)shall provide drainage from the sand filter, and Cleanouts(where
applicable) located on laterals and manifolds shall be free of obstruction, and accessible from the surface.
• Under-drain piping shall be cleared of sediment and debris when conveyance capacity is plugged.
Cleanouts may have been constructed for this purpose.
• Obstructions shall be removed from cleanouts without disturbing the filter media.
Overflow or Emergency Spillway conveys flow exceeding reservoir capacity to an approved stormwater
receiving system.
• Overflow spillway shall be cleared of sediment and debris when 50%of the conveyance capacity is
plugged.
• Source of erosion damage shall be identified and controlled when erosion channels are forming.
• Rocks or other armament shall be replaced when sand is exposed and eroding from wind or rain.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 90 of 133
Vegetation
• Vegetation,large shrubs or trees that limit access or interfere with sand filter operation shall be
pruned.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed.
• Nuisance or prohibited vegetation (such as blackberries or English Ivy)shall be removed when
discovered. Invasive vegetation contributing up to 25% of vegetation of all species shall be removed.
Debris and Litter shall be removed to ensure stormwater infiltration and to prevent clogging.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining sand filters shall be
provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the sand filter shall be safe and efficient. Egress and ingress routes shall be maintained to
design standards. Roadways shall be maintained to accommodate size and weight of vehicles,if
applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the facility shall be removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the sand filter. Pest control measures shall be taken when
insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito
larval development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system.Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the infiltration basin shall be filled.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 91 of 133
Soakage Trenches
Operations and Maintenance Plan
Soakage Trenches consist of drain rock and sand, and receive stormwater from roof downspouts and/or
area drains. There are various components within the system—piping,silt basin and the trench itself. The
Conveyance Piping consists of an inlet pipe (downspout or area drain),an outlet pipe located between
the silt basin and the soakage trench, and a perforated pipe,located on top of the aggregate bed of the
soakage trench. The Silt Basin is a structure receiving runoff from an inlet pipe and conveying it to the
soakage trench. The silt basin serves as the pre-treatment system for the soakage trench,removing
sediments and other debris that can impact its proper functioning.All facility components,vegetation, and
source controls shall be inspected for proper operations and structural stability. These inspections shall
occur, at a minimum,quarterly for the first two years from the date of installation,then two times per year
afterwards, or within 48 hours after each major storm. The facility owner must keep a log,recording all
inspection dates,observations,and maintenance activities.The following items shall be inspected and
maintained as stated:
Soakage trench infiltration: If water is noticed on top of the trench within 48 hours of a major storm,the
soakage trench may be clogged.
• Check for debris/sediment accumulation,rake and remove and evaluate upland causes(erosion,
surface or roof debris,etc.
• Assess the condition of the aggregate and the filter fabric in the trench. If there is sediment in the
aggregate,excavate and replace.
• If there is a tear in the filter fabric,repair or replace.
• The soakage trench area shall be protected from compaction during construction.
Conveyance Piping: If water ponds over the trench for more than 48 hours after a major storm and no
other cause if identified,it may be necessary to remove the filter fabric to determine if the perforated pipe
is clogged with sediment or debris.
• Any debris or algae growth located on top of the soakage trench should be removed and disposed of
properly.
• If the piping has settled more than I-inch,add fill material. If there are cracks or releases,replace or
repair the pipe. If there are signs of erosion around the pipe,this may be an indication of water
seeping due to a crack or break.
Silt Basin: If water remains in the soakage trench for 36-48 hours after storm,check for sediment
accumulation in the silt basin
• If less than 50%capacity remains in the basin or 6"of sediment has accumulated,remove and dispose
the sediment.
Spill Prevention:Virtually all sites,including residential and commercial,present dangers from spills.
All homes contain a wide variety of toxic materials including gasoline for lawn mowers, antifreeze for
cars,nail polish remover,pesticides, and cleaning aids that can adversely affect groundwater if spilled.It
is important to exercise caution when handling substances that can contaminate stormwater.
• Activities that pose the chance of hazardous materials ills shall not take place near soakage trenches.
A Shut-Off Valve or Flow-Blocking Mechanism may have been required with the construction of the
soakage trench to temporarily prevent stormwater from flowing into it,in the event of an accidental
material spill.This may also involve mats kept on-site that can be used to cover inlet drains in parking
lots. The shut-off valve shall remain in good working order,or if mats or other flow-blocking
mechanisms are used,they shall be kept in stock on-site.
Training and/or written guidance information for operating and maintaining soakage trenches shall be
provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the soakage trench is required for efficient maintenance.Egress and ingress routes will be
maintained to design standards at inspections.
Insects and Rodents shall not be harbored in the soakage trench.Pest control measures shall be taken
when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 92 of 133
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larva ides.These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the soakage trench shall be filled.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 93 of 133
Wet, Extended Wet, and Dry Ponds
Operations and Maintenance Plan
Wet Ponds are constructed ponds with a permanent pool of water.Pollutants are removed from
stormwater through gravitational settling and biologic processes. Extended Wet Ponds are constructed
ponds with a permanent pool of water and open storage space above for retention or short-term detention
of large storm events. Pollutants are removed from stormwater through gravitational settling and biologic
processes.Dry Ponds are constructed ponds with temporary storage for the retention or detention of large
storm events. The stormwater is stored and released slowly over a matter of hours.All facility
components,vegetation, and source controls shall be inspected for proper operations and structural
stability. These inspections shall occur,at a minimum,quarterly for the first 2 years from the date of
installation, and 2 times per year thereafter, and within 48 hours after each major storm event.The facility
owner must keep a log,recording all inspection dates,observations,and maintenance activities.The
following items shall be inspected and maintained as stated:
Pond Inlet shall assure unrestricted stormwater flow to the wet pond.
• Inlet pipe shall be cleared when conveyance capacity is plugged. Sources of sediment and debris shall
be identified and corrected.
• Determine if pipe is in good condition:
o If more than I inch of settlement, add fill material and compact soils.
o If alignment is faulty,correct alignment.
o If cracks or openings exist indicated by evidence of erosion at leaks,repair or replace pipe as
needed.
Forebay traps coarse sediments,reduces incoming velocity,and distributes runoff evenly over the wet
pond. A minimum I-foot freeboard shall be maintained.
• Sediment buildup exceeding 50% of the facility capacity shall be removed every 2-5 years or
sooner if performance is being affected.
Embankment, Dikes,Berms and Side Slopes retain water in the wet pond.
• Slopes shall be stabilized using appropriate erosion control measures when native soil is exposed or
erosion channels are forming.
• Structural deficiencies shall be corrected upon discovery:
o If cracks exist,repair or replace structure.
o If erosion channels deeper than 2 inches exist,stabilize surface. Sources of erosion damage shall be
identified and controlled.
Control Devices(e.g.,weirs,baffles,etc.)shall direct and reduce flow velocity. Structural deficiencies
shall be corrected upon discovery:
• If cracks exist,repair or replace structure.
Overflow Structure conveys flow exceeding reservoir capacity to an approved stormwater receiving
system.
• Overflow structure shall be cleared when 50%of the conveyance capacity is plugged. Sources of
sediment and debris shall be identified and corrected.
• Sources of erosion damage shall be identified and controlled when native soil is exposed at the top of
overflow structure or erosion channels are forming.
• Rocks or other armoring shall be replaced when only one layer of rock exists above native soil.
Sediment and Debris Management shall prevent loss of wet pond volume caused by sedimentation.
• Wet ponds shall be dredged when I foot of sediment accumulates in the pond.
• Gauges located at the opposite ends of the wet pond shall be maintained to monitor sedimentation.
Gauges shall be checked 2 times per year.
• Sources of restricted sediment or debris, such as discarded lawn clippings, shall be identified and
prevented.
• Debris in quantities sufficient to inhibit operation shall be removed routinely,e.g.no less than
quarterly,or upon discovery.
• Litter shall be removed upon discovery.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 94 of 133
Vegetation shall be healthy and dense enough to provide filtering while protecting underlying soils from
erosion and minimizing solar exposure of open water areas.
• Mulch shall be replenished at least annually.
• Vegetation,large shrubs or trees that limit access or interfere with wet pond operation shall be pruned
or removed.
• Grass(where applicable) shall be mowed to 4 inch-9 inch high and grass clippings shall be removed
if build up is damaging vegetation.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed if build up is
damaging vegetation.
• Nuisance or prohibited vegetation (such as blackberries or English Ivy)shall be removed when
discovered. Invasive vegetation contributing up to 25%of vegetation of all species shall be removed
and replaced.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when wet pond
function is impaired.Vegetation shall be replaced within 3 months,or immediately if required to
maintain cover density and control erosion where soils are exposed.If removing a dead or hazard tree
a permit maybe required,contact the City's Public Works Department for details on tree removal.
• Vegetation producing foul odors shall be eliminated.
Spill Prevention measures shall be exercised when handling substances that can contaminate stormwater
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining ponds shall be provided
to all property owners and tenants.A copy of the O&M Plan shall be provided to all property owners and
tenants.
Access to the wet pond shall be safe and efficient. Egress and ingress routes shall be maintained to design
standards. Roadways shall be maintained to accommodate size and weight of vehicles,if applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the wet pond shall be
removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the pond. Pest control measures shall be taken when
insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the pond shall be filled.
If used at this site, the following will be applicable:
Signage shall clearly convey information.
• Broken or defaced signs shall be replaced or repaired.
Fences shall be maintained to preserve their functionality and appearance.
• Collapsed fences shall be restored to an upright position.
• Jagged edges and damaged fences and shall be repaired or replaced.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 95 of 133
Constructed Treatment Wetlands
Operations and Maintenance Plan
Constructed Treatment Wetlands remove pollutants through several processes: sedimentation,
filtration,and biological processes.All facility components,vegetation,and source controls shall be
inspected for proper operations and structural stability. These inspections shall occur,at a minimum,
quarterly for the first 2 years from the date of installation,and 2 times per year thereafter,and within 48
hours after each major storm event. The facility owner must keep a log,recording all inspection dates,
observations,and maintenance activities.The following items shall be inspected and maintained as stated:
Wetland Inlet shall assure unrestricted stormwater flow to the wetland.
• Inlet pipe shall be cleared when conveyance capacity is plugged. Sources of sediment and debris shall
be identified and corrected.
• Determine if pipe is in good condition:
o If more than 1 inch of settlement, add fill material and compact soils.
o If alignment is faulty,correct alignment.
o If cracks or openings exist indicated by evidence of erosion at leaks,repair or replace pipe as
needed.
Forebay traps coarse sediments,reduces incoming velocity,and distributes runoff evenly over the
wetland.A minimum 1-foot freeboard shall be maintained.
• Sediment buildup exceeding 50%of the facility capacity shall be removed every 2-5 years or sooner
if performance is being affected.
Embankment, Dikes,Berms and Side Slopes retain water in the wetland.
• Slopes shall be stabilized using appropriate erosion control measures when native soil is exposed or
erosion channels are forming.
• Structural deficiencies shall be corrected upon discovery:
o If cracks exist,repair or replace structure.
o If erosion channels deeper than 2 inches exist,stabilize surface. Sources of erosion damage shall be
identified and controlled.
Control Devices(e.g.,weirs,baffles,etc.)shall direct and reduce flow velocity.
• Structural deficiencies shall be corrected upon discovery:
o If cracks exist,repair or replace structure.
Overflow Structure conveys flow exceeding reservoir capacity to an approved stormwater receiving
system.
• Overflow structure shall be cleared when 50%of the conveyance capacity is plugged. Sources of
sediment and debris shall be identified and corrected.
• Sources of erosion damage shall be identified and controlled when native soil is exposed at the top of
overflow structure or erosion channels are forming.
• Rocks or other armament shall be replaced when only one layer of rock exists above native soil.
Sediment and Debris Management shall prevent loss of wetland volume caused by sedimentation.
• Wetlands shall be dredged when I foot of sediment accumulates.
• Gauges located at the opposite ends of the wetland shall be maintained to monitor sedimentation.
Gauges shall be checked 2 times per year.
• Sources of restricted sediment or debris, such as discarded lawn clippings, shall be identified and
prevented.
• Debris in quantities sufficient to inhibit operation shall be removed routinely,e.g.no less than
quarterly,or upon discovery.
• Litter shall be removed upon discovery.
Vegetation shall be healthy and dense enough to provide filtering while protecting underlying soils from
erosion and minimizing solar exposure of open water areas.
• Mulch shall be replenished when needed.
• Vegetation,large shrubs or trees that limit access or interfere with wetland operation shall be pruned.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 96 of 133
• Nuisance or prohibited vegetation(such as blackberries or English Ivy)shall be removed when
discovered. Invasive vegetation contributing up to 25%of vegetation of all species shall be removed
and replaced.
• Dead vegetation shall be removed to maintain less than 10%of area coverage or when wetland
function is impaired. Vegetation shall be replaced within 3 months,or immediately if required to
maintain cover density and control erosion where soils are exposed.
• Vegetation producing foul odors shall be eliminated.
Spill Prevention measures shall be exercised when handling substances that can contaminate stormwater
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining treatment wetlands shall
be provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the wetland shall be safe and efficient.Egress and ingress routes shall be maintained to design
standards. Roadways shall be maintained to accommodate size and weight of vehicles,if applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the wetland shall be
removed.
• Gravel or ground cover shall be added if erosion occurs,e.g.,due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the constructed treatment wetland. Pest control measures
shall be taken when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
I. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the constructed treatment wetland shall be filled.
If used at this site, the following will be applicable:
Signage shall clearly convey information.
• Broken or defaced signs shall be replaced or repaired.
Fences shall be maintained to preserve their functionality and appearance.
• Collapsed fences shall be restored to an upright position.
• Jagged edges and damaged fences and shall be repaired or replaced.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 97 of 133
Underground Detention Tanks,Vaults and Pipes
Operations and Maintenance Plan
Underground Detention Tanks,Vaults,and Pipes are designed to fill with stormwater during large
storm events, slowly releasing it over a number of hours. There are numerous components to each system.
Drain Inlet Pipes convey stormwater into the detention facility. The Detention Chamber is the structure
in which stormwater accumulates during a storm event. Orifice Structure/Outlet Drain Pipe restricts
the flow out of the detention chamber,allowing it to fill up and slowly drain out. The orifice structure is
located at the downstream end of the detention chamber.Underground facilities shall be inspected
quarterly and within 48 hours after each major storm event.The facility owner must keep a log,recording
all inspection dates, observations, and maintenance activities. The following items shall be inspected and
maintained as stated:
Proprietary Structures such as oil-water separators, sedimentation manholes,grit chambers,etc. are
required to have an O&M plan submitted with material from the manufacturer for that specific product for
the O&M Agreement.
• If such material is not available or satisfactory for maintenance needs, city staff will assist
developer/property owner in preparing the O&M plan.
Drain Inlet Pipes shall be inspected for clogging or leaks where it enters the vault or basin during every
inspection and cleanout.
• Debris/sediment that is found to clog the inlet shall be removed,and disposed of in accordance with
applicable federal and state requirements.
Detention Chamber shall be inspected for cracks or damage during each inspection.
• The detention chamber shall be cleaned out yearly or after an inch of sediment has accumulated. If
there is a valve on the outlet pipe it shall be closed otherwise the outlet shall be plugged prior to
cleanout. Grit and sediment that has settled to the bottom of the chamber shall be removed during
each cleaning.
• Water and sediment in the detention chamber shall be removed, and disposed of in accordance with
regulations.
• Cleaning shall be done without use of detergents or surfactants.A pressure washer may be used if
necessary.
Orifice Structure/Outlet Drain Pipe shall be inspected for clogging during unit inspections/cleanouts.
• Debris/sediment that is found to clog the inlet shall be removed,and disposed of in accordance with
applicable federal and state requirements.
Vegetation such as trees should not be located in or around the detention facility because roots from trees
can penetrate the unit body, and leaves from deciduous trees and shrubs can increase the risk of clogging
the intake pipe.
• Large shrubs or trees that are likely to interfere with detention facility operation shall be identified at
each inspection then removed.
Source Control measures typically include structural and non-structural controls. Non-structural controls
can include street sweeping and other good housekeeping practices.It is often easier to prevent pollutants
from entering stormwater than to remove them.
• Source control measures shall be inspected and maintained(where applicable).
Spill Prevention procedures require high-risk site users to reduce the risk of spills.However,virtually all
sites,including residential and commercial,present dangers from spills. Homes contain a wide variety of
toxic materials including gasoline for lawn mowers, antifreeze for cars,pesticides, and cleaning aids that
can adversely affect storm water if spilled. It is important for everyone to exercise caution when handling
substances that can contaminate stormwater. Spill prevention procedures shall be implemented in areas
where there is likelihood of spills from hazardous materials.
Training and/or written guidance information for operating and maintaining detention facilities shall
be provided to all property owners and tenants. A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the detention facility is required for efficient maintenance. Egress and ingress routes shall be
open and maintained to design standards.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 98 of 133
Signage may serve to educate people about the importance or function of the site's stormwater protection
measures. Signs may also discourage behavior that adversely impacts the stormwater protection measures
and encourages behavior that enhances or preserves stormwater quality. If debris is a problem,a sign
reminding people not to litter may partially solve the problem. Signage (where applicable)will be
maintained and repaired as needed during or shortly after inspections.
Insects and Rodents shall not be harbored in the detention facility. Pest control measures shall be taken
when insects/rodents are found to be present
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system.Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the detention facility shall be filled.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 99 of 133
Drywells
Operations and Maintenance Plan
Drywells are designed to infiltrate stormwater into the ground. Stormwater is piped to drywells from roof
downspouts or pollution control facilities such as swales or planters. The pollution control facility is
designed to settle out sediments and separate oils and greases from the water before releasing it through a
pipe to the drywell. This prolongs the life of the drywell and helps to prevent the contamination of soils
and groundwater. The drywell is a concrete or plastic manhole section with many small holes in the sides
to allow stormwater to infiltrate into the surrounding soil. The drywell system shall be inspected and
cleaned quarterly and within 48 hours after each major storm event.The facility owner must keep a log,
recording all inspection dates,observations, and maintenance activities.Drywells are considered
Underground Injection Wells in Oregon and are subject to State regulations for permitting and testing by
the Oregon DEQ. The following items shall be inspected and maintained as stated:
Stormwater Drain Pipe shall be inspected for clogging or leaks where it enters the drywell.
• Debris/sediment that is found to clog the pipe shall be removed and disposed of in accordance with
applicable federal and state requirements.
Drywell shall be inspected during each cleanout. Ponding around the catch basins or sedimentation
manhole or drywell lids may indicate that the drywell is failing due to siltation,or the clogging of the
sediment pores surrounding the drywell. Clogged drywells must be replaced.
Vegetation such as trees should not be located in or around the drywell because roots from trees can
penetrate the unit body, and leaves from deciduous trees and shrubs can increase the risk of clogging the
intake pipe.
• Large shrubs or trees that are likely to interfere with operation will be identified at each inspection
and removed.
Source Control measures typically include structural and non-structural controls.Non-structural controls
can include parking lot or street sweeping and other good housekeeping practices.It is often easier to
prevent pollutants from entering stormwater than to remove them.
• Source control measures shall be inspected and maintained(where applicable).
Spill Prevention procedures require high-risk site users to reduce the risk of spills.However,virtually all
sites,including residential and commercial,present dangers from spills.Homes contain a wide variety of
toxic materials including gasoline for lawn mowers, antifreeze for cars,solvents,pesticides, and cleaning
aids that can adversely affect storm water if spilled.It is important to exercise caution when handling
substances that can contaminate stormwater. Spill prevention procedures shall be implemented in areas
where there is likelihood of spills from hazardous materials.
A Shut-Off Valve or Flow-Blocking Mechanism may have been required with the construction of the
drywell to temporarily prevent stormwater from flowing into it,in the event of an accidental material
spill. This may also involve mats kept on-site that can be used to cover inlet drains in parking lots.The
shutoff valve shall remain in good working order,or if mats or other flow-blocking mechanisms are used,
they shall be kept in stock on-site.
Training and/or written guidance information for operating and maintaining drywell systems shall be
provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the drywell is required for efficient maintenance. Egress and ingress routes shall be open and
maintained to design standards.
• City inspection staff may require owners to provide proof of registration,permitting and maintenance
logs for the facility as required by the Oregon DEQ.
Insects and Rodents shall not be harbored in the drywell. Pest control measures shall be taken when
insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the Ci 's inspector.Acceptable methods include but are not limited to the
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 100 of 133
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system.Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the drywell shall be filled.
Signage may serve to educate people about the importance or function of the site's stormwater protection
measures. Signs may also discourage behavior that adversely impacts the stormwater protection measures
and encourages behavior that enhances or preserves stormwater quality. If debris is a problem,a sign
reminding people not to litter may partially solve the problem. Signage (where applicable) shall be
maintained and repaired as needed during or shortly after inspections.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 101 of 133
Spill Control Manholes
Operations and Maintenance Plan
Spill Control Manholes operate using the principal that oil and water are immiscible (do not mix) and
have different densities. Oil,being less dense than water,floats to the surface. The spill control manhole
shall be inspected and cleaned quarterly. The facility owner must keep a log,recording all inspection
dates,observations, and maintenance activities.The following items shall be inspected and maintained as
stated:
Stormwater Drain Inlet Pipe shall be inspected for clogging or leaks where it enters the manhole during
every inspection and cleanout.Debris/sediment that is found to clog the inlet shall be removed,tested,
and disposed of in accordance with applicable federal and state requirements.
Manhole Chamber shall be inspected for cracks or damage during each inspection.
• The manhole shall be cleaned out quarterly.Cleanout shall be done in a manner to minimize the
amount of trapped oil entering the outlet pipe. If there is a valve on the outlet pipe it shall be closed
otherwise the outlet will be plugged prior to clean-out.
• Water and oil shall be removed,tested,and disposed of in accordance with regulations.Grit and
sediment that has settled to the bottom of the chamber shall be removed during each cleaning
• Cleaning shall be done without use of detergents or surfactants.A pressure washer along with a
vacuum may be used if necessary.
Absorbent Pillows and Pads(where applicable)absorb oil from the separation chamber.
• Replacement shall occur at least twice a year,in the spring and fall,or as necessary to retain oil-
absorbing function.
Stormwater Drain Outlet Pipe shall be inspected for clogging or leaks where it exits the manhole.
Particular attention shall be paid to ensure that the joint where the tee joins the outlet pipe is watertight.
• Debris/sediment that is found to clog the outlet shall be removed,tested,and disposed of in
accordance with applicable federal and state requirements.
Vegetation such as trees should not be located in or around the spill control manhole because roots can
penetrate the unit body, and leaves from deciduous trees and shrubs can increase the risk of clogging.
• Large shrubs or trees that are likely to interfere with manhole operation shall be identified at each
inspection and removed.
Source Control measures typically include structural and non-structural controls.Non-structural controls
can include street sweeping and other good housekeeping practices.
• Source control measures shall be inspected and maintained.
Spill Prevention procedures require high-risk site users to reduce the risk of spills. However,virtually
all sites,including residential and commercial,present dangers from spills. Homes contain a wide variety
of toxic materials including gasoline for lawn mowers,antifreeze for cars,pesticides, and cleaning aids
that can adversely affect storm water if spilled. It is important to exercise caution when handling
substances that can contaminate stormwater. Spill prevention procedures shall be implemented in areas
where there is likelihood of spills from hazardous materials.
Training and/or written guidance information for operating and maintaining spill control manholes
shall be provided to all property owners and tenants.A copy of the O&M Plan shall be provided to all
property owners and tenants.
Access to the spill control manhole is required for efficient maintenance. Egress and ingress routes shall
be open and maintained to design standards.
Insects and Rodents shall not be harbored in the spill control manhole. Pest control measures shall be
taken when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors,the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non-chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector.Acceptable methods include but are not limited to the
following:
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 102 of 133
I. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non-chemical methods have proved unsuccessful,contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israeliensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the manhole shall be filled.
Signage may serve to educate people about the importance or function of the site's stormwater protection
measures. Signage (where applicable)shall be maintained and repaired as needed during or shortly after
inspections.
Appendix E—Operations and Maintenance
Stormwater Post-Construction Requirements Update Ordinance No. 6464
Exhibit A Page 103 of 133
APPENDIX F—APPROVED VEGETATION LIST
Facility Planting Zones
Zone A:Area of the facility defined as the bottom of the facility to the designated high-water mark. This area
has wet to moist soils and plants located here shall be tolerant of mild inundation.
Zone B:Area of the facility defined as the side slopes from the designated high-water mark up to the edge of the
facility. This area typically has drier to moist soils with the moist soils being located farther down the side
slopes.Plants here should be drought tolerant and help stabilize the slopes.
Swale Planting Zones
Zone B
Zone A
Zone B
Planter Planting Zones
Zone A
Rain Garden Planting Zones
Zone B
Zone A
Zone B
Appendix F—Approved Vegetation List
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 104 of 133
Facility Plant List
Note:Alternative plants not found on this list may be approved based on ease of maintenance and beneficial
impacts to water and soil quality.Non-native invasive plants are not allowed. Only native plants are allowed in
stormwater facilities within Natural Resource Protection Area setbacks (SDC 4.3-117.F.4). Each stormwater
facility must have a minimum of three unique species.
X=yes,blank=no
Scientific Name Common Name
i~ a
A.
v�i � a � � 3 E � � � x •� o
m v C7 W d A Z q ar Un W
*approved for o 0 3 > o U a
public facilities C7 r) rn pC N N Z C7 W w O n
Agrostis exarata Spike Bentgrass X X X 36" Seed Full to
Part
Alisma Water Plantain X X X X 24" 12" Full
plantago-
aquatica var.
americanum
Allium Hooker's Onion X X X X 12" 12" Full
acuminatum
Allium Slim Leaf Onion X X X X X X 12" 12" Full
am lectens
Arctostaphylos Kinnickinnick X X X X X X X 6" 12" Full to
uva-ursi* Part
Asclepias Showy X X X X X X X X 48" 36" Full
s eciosa Milkweed
m Aster halhi Hall's Aster X X X X X 36" 18" Full
p' Aster sus icatus Douglas Aster X X X X X 36" 18" Full
m
c Athyrium felix- Lady Fern X X X X X 36" 24" Shade
emin
Beckmania American Slough X X X X 36" Seed Full
s zi achne Grass 12"
Bidens cernua Nodding X X X X 24" 12" Full to
Beggerticks Part
Blechnum Deer Fern X X X X X X 24" 24" Shade
s icant
Brodiaea Harvest Brodiaea X X X X 36" 12" Full
coronaria
Bromus California Brome X X X X 18" Seed Full to
carinatus Grass Part
Bromus Alaska Brome X X X 18" Seed Full to
sitchensis Part
Bromus vulgaris Columbia Brome X X X 18" Seed Full to
Part
Carex densa* Dense Sedge X X X X X X X 24" 12" Full to
Part
Appendix F—Approved Vegetation List
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 105 of 133
Carex Dewey Sedge X X X X X X 36" 12" Part to
dewe anna Shade
Carex Henderson Sedge X X X X X 40" 12" Full to
hendersonii Part
Carex obnupta* Slough Sedge X X X X X X X X 4' 12" Full to
Part
Carex stipata* Sawbeak Sedge X X X X X X X 20" 12" Full to
Part
Carex Foothill Sedge X X X X X X X X 24" 12" Full to
tumulicola* Shade
Carex Lateral Sedge X X X X X X X 24" 12" Full to
unilateralis I I I Part
Carex vesicaria Inflated Sedge X X X X X X X X 36" 12" Part
Danthonia California X X X 18" Seed Full to
calf ornica Oat grass 12" Part
Deschampsia Tufted Hair X X X X X X X 36" Seed Full to
ces itosa Grass 12" Part
Eleocharis Needle Spike X X X X X X X X 30" 12" Part
s~ acicularis Rush
p, Eleocharis Ovate Spike X X X X X X X X X 30" 12" Part
a
ovata Rush
Eleocharis Creeping Spike X X X X X X X X 30" 12" Part
alustris Rush
Elymus glaucus Blue Wild Rye X X X X 24" Seed Full to
►�+" Part
Eriophyllum Oregon Sunshine X X X X X X 18" 12" Full
lanatum
Festuca Western Fescue X X X 24" Seed Full to
occidentalis Grass I Part
Festuca roemeri Roemer's Fescue X X X X X X X 24" Seed Full
var. roemeri 12"
Festuca rubra Red Fescue X X X 24" Seed Full to
Part
Fragaria Coastal X X X X X X X X 6" 12" Full to
chiloensis* Strawberry Part
Fragaria vesca Woodland X X X X X X X X 6" 12" Full to
Strawberry Part
Fragaria Wild Strawberry X X X X X X X X 6" 12" Full to
vir iniana Part
Glyceria Western Manna X X X 18" Seed Part
occidentalis Grass
Grindelia Gumweed X X X X X 30" 12" Full
inte ri olia
Hordeum Meadow Barley X X X 30" Seed Full
brachyantherum
Iris Douglas Iris X X X X X X 18" 12" Full to
dou lasiana* Part
Iris tenax* Oregon Iris X X X X X X 18" 12" Full to
Part
Juncus Tapertip Rush X X X X X X X 24" 12" Full
acuminatus*
Juncus balticus Baltic Rush X X X X X X X X 20" 12" Full to
Part
Juncus a usus Common/Soft X X X X X X X X 36" 12" Full to
Appendix F—Approved Vegetation List
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 106 of 133
van racilis* Rush Part
Juncus effusus Common Rush X X X X X X X X 36" 12" Full to
van pacificus* Part
Juncus Dagger-leaf X X X X X X X 10" 12" Full to
ensi olius* Rush Part
Juncus oxymeris Pointed Rush X X X X X X X X X 24" 12" Full to
Part
Juncuspatens* Spreading or X X X X X X X X 36" 12" Full to
Grooved Rush Part
Juncus tenuis Slender Rush X X X X X X X X X 36" 12" Full to
Part
Koeleria Junegrass X X X X 24" Seed Full
macrantha
Lupinus Large-leaved X X X X X X X 12" 12" Full to
polyphyllus Lupine Part
Lupinus Riverbank X X X X X X X 36" 24" Full
rivularis Lupine
Olsynium Purple-eyed X X X X X X X 12" 24" Full to
douglasii Grass Part
Polystichum Sword Fern X X X X X X X 24" 24" Part to
munitum Shade
Rubus Creeping X X X X X X X X 12" Full to
calycinoides* Bramble Part
( entalobus)
Sagittaria Wapato X X X 24" 12" Full
lati olia
Solidago Canada X X X X X X 4 24" Full to
canadensis Goldenrod Part
Schoenoplectus Hardstem X X X X X 5' 12" Full
acutus var. Bulrush
acutus
Schoenoplectus American X X X X X 7' 12" Full
americanus Bulrush
Schoenoplectus Small Fruited X X X X X X X X 24" 12" Full to
microcarpus Bulrush Part
Schoenoplectus Softstem Bulrush X X X X X X X X 5' 24" Full to
validus Part
Sidalcea Meadow X X X X X X X X 36" 12" Full to
cam estris Sidalcea Part
Sisyrinchium Blue-eyed Grass X X X X X X X X 6" 12" Full to
idahoense I Part
Viola glabella Stream Violet X X X X X X X 4" 6" Full to
Part
Cornus sericea Kelsey X X X X X 24" 24" Full to
'Kelseyii'* Dogwood Part
a
Gaultheria Salal X X X X X 24" 24" Part
shallon
Mahonia Dull X X X X X X 24" 24" Part
nervosa* Oregon Grape
cr Mahonia Creeping X X X X X X 18" 18" Part
repens* Oregon Grape
Spiraea Birchleaf Spiraea X X X X X X X 3' 24" Full to
betuli olia Part
Spiraea spp.* Dwarf Spirea X X X X X X 3' 3' Full
Appendix F—Approved Vegetation List
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 107 of 133
Symphoricarpos Common X X X X X X 4' 3' Full to
alba Snowberry Part
Ceanothus Buckbrush X X X X X X X 7' 7' Full
cuneatus
Ceanothus Deerbrush X X X X 13' 10' Full to
integerrimus I I Part
Ceanothus Oregon Redstem X X X X X X X 7' 4' Full
san uineus Ceanothus
o Ceanothus Snowbrush X X X X X X X 5' 3' Full
s�
velutinus
Qn
Cornus sericea Red-twig X X X X X X X X 6' 6' Full to
Dogwood Part
*4 Holodiscus Oceanspray X X X X X X 6' 6' Full to
discolor Part
Lonicera Black Twinberry X X X X X X X 5' 4' Full to
involucrata Part
Mahonia Tall Oregon X X X X X X X 5' 3' Full to
(Berberis) Grape Part
aquifolium
Morella Pacific Wax X X X X X X X X 10' 10' Full to
(Myrica) Myrtle Part
calf ornica
Oemleria Osoberry X X X X X X 6' 4' Full to
cerasi ormis Part
Philadelphus Wild Mock X X X X X 6' 4' Full to
lewisii Orange Part
Physocarpus Pacific Ninebark X X X X X X X X 10' 5 Full to
ca itatus Part
Ribes Red-flowering X X X X X X X 8' 4' Full to
a
san uineum Currant Part
Rubus Thimbleberry X X X X X X X X 8' 4' Full to
cn
parviflorus I Part
Rubus Salmonberry X X X X X X X 10' 4' Full to
a s ectabilis Part
Salix lucida var. Pacific Willow X X X 13' 6' Full
'Lasiandra'
Sambucus nigra Blue Elderberry X X X X X X 10' 10' Full to
ssp. cerulea Part
Sambucus Red Elderberry X X X X X X 10' 10' Full to
racemosa Part
Spiraea Douglas Spiraea X X X X X X 7' 4' Full to
douglasii Part
Viburnum edule Highbush X X X X X X 6' 6' Full to
Cranberry Part
*Approved street tree species
F� Abies koreana Silver Korean Fir X X X X X X 50' Full to
Part
*Acer Vine Maple X X X X X X X X 15' 10' Full to
circinatum Part
*Acer griseum Paperbark Maple X X X X X 30' Full to
Part
Alnus White Alder X X X XLX
XLX
100' Full to
rhombi olia Part
Alnus rubra Red Alder X X X X X 80' Full to
Appendix F—Approved Vegetation List
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 108 of 133
Part
Amelanchier Western X X X X X X 20' 10' Full to
alnifolia (Saskatoon) Part
Serviceberry
*Amelanchier x Apple X X X X X 25' Full to
grandiflora Serviceberry Part
Arbutus x Marina X X X X X X 40' Full to
Marina' Strawberry Tree Part
Arbutus Madrone X X X X X X X 35' Full
menziesii
*Arbutus unedo Strawberry X X X X X 15' Full
Madrone
*Carpinus European X X X X 40' Full
betulus Hornbeam
*Celtis Common X X X X X X 100' Full to
occidentalis Hackberry Part
Celtis reticulata Netleaf X X X X X 25' Full to
Hackbe Part
*x Chitalpa Chitalpa X X X X x 35' Full to
tashkentensis I Part
Cornus nuttalii Western X X X X X X 20' Full to
(and hybrids) Flowering Part
Dogwood
Corylus cornuta Western Beaked X X X X X X X 15' Full to
Hazelnut Part
Crataegus Black Hawthorn X X X X 40' 10' Full
dou lasii
*Lagerstroemia Crepe Myrtle X X X X X 15' Full
indica x fauriei
F Malus fusca Pacific X X X X X X 30' 10' Full to
F� Crabapple Part
*Nyssa Black Tupelo X X X X X 75' Full to
s lvatica Part
*Parrotia Persian X X X X X 50' Full to
persica Ironwood Part
*Pistacia Chinese Pistache X X X X 35' Full
chinesis
*Quercus Swamp White X X X X X X 60' Full to
bicolor Oak Part
*Quercus Blue Oak X X X X X 80' Full to
douglasii I Part
*Quercus Oregon White X X X X X X 100' Full to
garryana Oak Part
Quercus California Black X X X X X X 100' 20' Full to
kelloggii Oak Part
*Quercus Shumard Oak X X X X X X 60' Full
shumardii
Quercus suber Cork Oak X X X X X X 100' Full
Rhamnus Cascara X X X X X X X 30' Full to
urshiana Part
Taxodium Bald Cypress X X X X X 100' Full
distichum
Appendix F—Approved Vegetation List
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 109 of 133
APPENDIX G
APPROVED STREET TREE LIST
Ordinance No. 6464
Exhibit A Page 110 of 133
APPENDIX G
APPROVED STREET TREE LIST
Street Trees for Under Powerlines
Botanical Name Common Name
Acer ginnala Amur Maple
Acer Grandidentatum Bigtooth Maple
Acer tartaricum Tartarian Maple
Acer truncatum Shantung Maple
Amelanchier arborea Shadbush
Amelanchier x grandiora 'var.' 'Autumn Brilliance' Serviceberry
Amelanchier x grandiora 'var.' 'Robin Hill' Serviceberry
Amelanchier leavis Smooth Shadbush, Smooth Serviceberry
Arbus unedo Strawberry Tree
Carpinus Caroliana American Hornbeam
Cercis Redbud most varieties
Clerodendrum trichotomum Glorybower Tree
Cornus florida Flowering Dogwood
Cornus kousa Korean Dogwood
S rin a reticulata 'var.' 'Summer Snow' Ja anese Tree Lilac
Ordinance No. 6464
Exhibit A Page 111 of 133
Street Trees for Parking Strips 4 Feet to 6 Feet Wide
Botanical Name Common Name
Acer campestre Hedge Maple
Acer campestre 'var.' 'Queen Elizabeth' Hedge Maple
Acer cappadocicum Coliseum Maple
Acer grandidentatum Bigtooth Maple
Acer griseum Paperbark Maple
Acer platanoides 'var.' 'Olmsted'Norway Maple
Acer rubrum Red Maple
Acer rubrum Armstrong' 'Armstrong' Red Maple
Acer rubrum 'var.' 'Autumn Flame' Red Maple
Acer rubrum 'var.' 'Bowhall' Red Maple
Acer rubrum 'var.' 'Karpick' Red Maple
Acer rubrum 'var.' 'October Glory' Red Maple
Acer rubrum 'var.' 'Red Sunset' Red Maple
Acer x freemanii 'var.' 'Armstrong II'Maple
Acer x freemanii 'var.' 'Autumn Blaze' Maple
Acer x freemanii 'var.' 'Autumn Fantasy'Maple
Acer x freemanii 'var.' 'Scarlet Sentinel' Maple
Aesculus x carnea 'var.' 'Briotti' Red Horsechestnut
Aesculus x carnea 'var.' 'Ft. McNair' Red Horsechestnut
Amelanchier x grandiora Serviceberry
Amelanchier x grandiora 'var.' 'Cumulus' Serviceberry
Betula jacquemontii Jacquemontii Birch
Carpinus betulus 'var.' 'Fastigiate' European Hornbeam
Carpinus carolinia American Hornbeam
Celtis laevigata 'var.,' 'All Seasons' Sugar Hackberry
Celtis occidentalis Hackberry
Celtis occidentalis 'var.' 'Chicagoland' Hackberry
Celtis occidentalis 'var.' 'Prairie Pride' Hackberry
Cercidiphyllum japonica Katsura
Cercis canadensis Redbud
Chionanthus virginicus Fringe Tree
Chitalpa tashkentensis Chitalpa
Cornus nuttallii Pacific Dogwood
Koelreuteria paniculata Goldenrain Tree
Ostrya virginiana American Hop Hornbeam
Parrotia persica Persian Parrotia
Ordinance No. 6464
Exhibit A Page 112 of 133
Street Trees for Parking Strips 6 Feet to 8 Feet Wide
Botanical Name Common Name
Acer campestre Hedge Maple
Acer campestre 'var.' 'Queen Elizabeth' Hedge Maple
Acer cappadocicum Coliseum Maple
Acer rubrum Red Maple
Acer rubrum 'var.' 'Autumn Flame' Red Maple
Acer rubrum 'var.' 'Bowhall' Red Maple
Acer rubrum 'var.' 'Karpick' Red Maple
Acer rubrum 'var.' 'October Glory' Red Maple
Acer rubrum 'var.' 'Red Sunset' Red Maple
Acer saccharum Sugar Maple
Acer saccharum 'var.' 'Legacy' Sugar Maple
Acer saccharum 'var.' 'Bonfire' Sugar Maple
Acer saccharum 'var.' 'Commemoration' Sugar Maple
Acer saccharum 'var.' 'Green Mountain' Sugar Maple
Acer saccharum 'var.' 'Seneca Chief Sugar Maple
Acer truncatum x 'var.' 'Norwegian Sunset'Maple
Acer truncatum x 'var.' 'Pacific Sunset'Maple
Acer x freemanii 'var.' 'Autumn Blaze' Maple
Acer x freemanii 'var.' 'Autumn Fantasy' Maple
Acer x freemanii 'var.' 'Celebration'Maple
Acer x freemanii 'var.' 'Scarlet Sentinel'Maple
Aesculus hippocastanum 'var.' 'Bauman' Horsechestnut
Aesculus x carnea 'var.' 'Briotti' Red Horsechestnut
Aesculus x carnea 'var.' 'Ft. McNair' Red Horsechestnut
Castenea Dentata Blight Resistant Chestnut
Carpinus betulus European Hornbeam
Carpinus betulus 'var.' 'Fastigiate' European Hornbeam
Carpinus carolinia American Hornbeam
Celtis laevigata 'var.,' 'All Seasons' Sugar Hackberry
Celtis occidentalis Hackberry
Celtis occidentalis 'var.' 'Chicagoland' Hackberry
Celtis occidentalis 'var.' 'Prairie Pride' Hackberry
Ordinance No. 6464
Exhibit A Page 113 of 133
Street Trees for Parking Strips 6 Feet to 8 Feet Wide (continued)
Botanical Name Common Name
Ginkgo biloba Ginkgo Male Only
Ginkgo biloba 'var.' 'Autumn Gold Ginkgo Male only
Ginkgo biloba 'var.' 'Lakeview' Ginkgo Male only
Ginkgo biloba 'var.' 'Magyar' Ginkgo male only
Halesia carolina Carolina Silverbell
Halesia monticola Mountain Silverbell
Koelreuteria paniculata Goldenrain Tree
Ostrya virginiana American Hop Hornbeam
Quercus robur English Oak
Quercus robur 'var.' 'Skymaster' English Oak
Quercus rubra Northern Red Oak
Quercus garryana Oregon White Oak
Quercus shumardii Shumard Oak
Sophora japonica Scholartree
Sophora japonica 'var.' 'Princeton Upright' Scholartree
Sophora japonica 'var.' 'Regent' Scholartree
Umbellularia californica Oregon Myrtle
Zelkova serrata Japanese Zelkova
Zelkova serrata 'var.' 'Green Vase' Japanese Zelkova
Zelkova serrata 'var.' 'Halka' Japanese Zelkova
Zelkova serrata 'var.' 'Village Green' Japanese Zelkova
Ordinance No. 6464
Exhibit A Page 114 of 133
Street Trees for Parking Strips 10 Feet Wide and Larger
Botanical Name Common Name
Acer macrophyllum Bigleaf Maple
Acer nigrum Black Maple
Acerpseudoplatanus Sycamore Maple
Acerpseudoplatanus 'var.' 'Lustre' Sycamore Maple
Acerpseudoplatanus 'var.' 'Spaethii' Sycamore Maple
Acer saccharum Sugar Maple
Acer saccharum 'var.' 'Legacy' Sugar Maple
Acer saccharum 'var.' 'Bonfire' Sugar Maple
Acer saccharum 'var.' 'Commemoration' Sugar Maple
Acer saccharum 'var.' 'Green Mountain' Sugar Maple
Acer saccharum 'var.' 'Seneca Chief Sugar Maple
Aesculus hippocastanum 'var.' 'Bauman' Horsechestnut
Castenea dentata Blight Resistant Chestnut
Carpinus betulus European Hornbeam
Celtis laevigata Sugar Hackberry
Cladrastis lutea Yellowwood
Eucommia ulmoides Hardy Rubber Tree
Ginkgo biloba Ginkgo male only
Ginkgo biloba 'var.' 'Autumn Gold' Ginkgo male only
Ginkgo biloba 'var.' 'Lakeview' Ginkgo male only
Ginkgo biloba 'var.' 'Magyar' Ginkgo male only
Ginkgo biloba 'var.' 'Princeton Sentry' Ginkgo male only
Gymnocladus dioicus Kentucky Coffeetree
Gymnoclaudus dioicus 'var.' 'Expresso' Kentucky Coffeetree
Halesia carolina Carolina Silverbell
Liriodendron tulipifera Tulip Tree
Lithocarpus densiflorus Tanbark Oak
Magnolia grandiflora Southern Magnolia
Nyssa sylvatica Blackgum
Quercus bicolor Swamp White Oak
Quercus coccinea Scarlet Oak
Quercus douglassi Blue Oak
Quercus lobata Valley Oak
Quercus frainetto 'var.' 'Forest Green' Hungarian Oak-
Quercus macrocarpa Bur Oak
Quercus phellos Willow Oak
Quercus robur English Oak
Quercus robur 'var.' 'Skymaster' English Oak
Quercus rubra Northern Red Oak
Quercus shumardii Shumard Oak
Sophora japonica Scholartree
Sophora japonica 'var.' 'Princeton Upright' Scholartree
Sophora japonica 'var.' 'Regent' Scholartree
Tilia americana American Linden
Tilia americana 'var,' 'Redmond'American Linden
Ordinance No. 6464
Exhibit A Page 115 of 133
Street Trees for Parking Strips 10 Feet Wide and Larger
Botanical Name Common Name
Tilia americana 'var.' 'Legend' American Linden
Tilia tomentosa Silver Linden
Tilia platyphyllos Bigleaf Linden
Tilia x euchlora Crimean Linden
Ulmus accolade Accolade Elm Dutch elm disease tolerant only
Ulmus parvifolia Chinese Elm Dutch elm disease tolerant only
Umbellularia californica Oregon Myrtle
Zelkova serrata Japanese Zelkova
Zelkova serrata 'var.' 'Green Vase' Japanese Zelkova
Zelkova serrata 'var.' 'Halka' Japanese Zelkova
Zelkova serrata 'var.' 'Village Green' Japanese Zelkova
Ordinance No. 6464
Exhibit A Page 116 of 133
APPENDIX H
Onsite Source Stormwater Controls
(A) Overview
(1) Some site characteristics and uses may generate specific pollutants that are not
addressed solely through implementation of the stormwater quality measures
identified in 4.3.110. The site characteristics and uses in this chapter have been
identified as potential sources for chronic loadings or acute releases of pollutants
such as oil and grease, toxic hydrocarbons, heavy metals, toxic compounds,
solvents, abnormal pH levels, nutrients, organics, bacteria, chemicals, and
suspended solids. This appendix presents source controls for managing these
pollutants at their source.
(2) Industrial facilities may be subject to additional requirements through State of
Oregon issued NPDES permits or as outlined in Oregon Administrative Rules
(OAR) 340 Division 041.
(3) Springfield Municipal Code 4.372 lists prohibited discharges to the City's storm
sewer system. The City has used these standards in the development of the
listed source controls so stormwater discharges can better meet these criteria.
The implementation of this chapter is in addition to the applicable water quality,
flow control, and flood control requirements.
(4) Applicants may propose alternatives to the source controls identified in this
chapter. Proposal of an alternative source control or alternative design element
will require an additional review process and may delay issuance of related
building or public works permits.
(B) Site Uses and Characteristics That Trigger Source Controls
(1) As provided in SDC 4.3.110(C)(8), development that includes any of the following
uses and characteristics are subject to the design methodologies of this chapter:
(a) Fuel Dispensing Facilities and Surrounding Traffic Areas (Section C)
(b) Above-Ground Storage of Liquid Materials (Section D)
(c) Solid Waste Storage Areas, Containers, and Trash Compactors (Section
E)
(d) Outdoor Storage of Bulk Materials (Section F)
(e) Material Transfer Areas/Loading Docks (Section G)
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 117 of 133
(f) Equipment and/or Vehicle Washing Facilities (Section H)
(g) Covered Vehicle Parking Areas (Section 1)
Applicants are required to address all of the site characteristics and uses listed in
Sections (C) through (1). For example, if a development includes both a fuel
dispensing area and a vehicle washing facility, the source controls in both
Sections (C) and (H) will apply.
(2) Source Control Goals and Objectives
(a) The specific source control standards are based on the following goals
and objectives:
(i) Prevent stormwater pollution by eliminating pathways that may
introduce pollutants into stormwater.
(ii) Protect soil, groundwater and surface water by capturing acute
releases and reducing chronic contamination of the environment.
(iii) Direct wastewater discharges (including wash water) to a sanitary
sewer system.
(iv) Direct areas that have the potential for acute releases or
accidental spills, and are not expected to regularly receive flow or
require water use (such as covered fuel islands or covered
containment areas), to an approved method of containment or
destination.
(v) Safely contain spills on-site, avoiding preventable discharges to
sanitary sewer facilities, surface water bodies, or underground
injection control structures (UICs).
(vi) Emphasize structural controls over operational procedures.
Structural controls are not operator dependent and are considered
to provide more permanent and reliable source control. Any
proposals for operation-based source controls need to describe
the long-term viability of the maintenance program.
(3) Signage
(a) Informational signage is required for certain site uses and activities that
may pollute stormwater. Signage addresses good housekeeping rules
and provides emergency response measures in case of an accidental
spill. Required spill response supplies must be clearly marked, located
where the signage is posted (or the location of the supplies must be
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 118 of 133
clearly indicated by the signage), and must be located near the high-risk
activity area. Required spill response supplies, such as absorbent
material and protective clothing, should be available at all potential spill
areas. Employees must be familiar with the site's operations and
maintenance plan and proper spill cleanup procedures.
(b) All signage must conform to the standards described below. Additional
signage for specific activities is noted in applicable Sections C through I.
(c) Signs must be 8.5" x 11" or larger and located and plainly visible from all
activity areas. More than one sign may be needed to accommodate larger
activity areas. Signs must be water-resistant and include the following
information:
(i) Safety precautions for self-protection and spill containment.
(ii) Immediate spill response procedures—for example: "Turn the
valve located at..." or "Use absorbent materials"
(iii) Emergency contact(s) and telephone number(s)—for example:
"Call 911" and "City of Springfield Public Works"
(C) Fuel Dispensing Facilities
(1) Fuel Dispensing Facilities include areas where fuel is transferred from bulk
storage tanks to vehicles, equipment, and/or mobile containers (including fuel
islands, above ground fuel tanks, fuel pumps, and the surrounding pad). This
applies to large-sized gas stations as well as single-pump fueling operations.
(2) Cover
(a) The fuel dispensing area must be covered with a permanent canopy, roof,
or awning so precipitation cannot come in contact with the fueling activity
areas. Rainfall must be directed from the cover to an approved
stormwater destination.
(b) Covers 10 feet high or less must have a minimum overhang of 3 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated fueling activity area/pad it is to cover.
(c) Covers higher than 10 feet must have a minimum overhang of 5 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated fueling activity area/pad it is to cover.
(3) Pavement
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 119 of 133
(a) A paved fueling pad must be placed under and around the fueling activity
area with asphalt or concrete and must meet all applicable building code
requirements.
(b) Sizing of the paved areas must be adequate to cover the activity area,
including placement and number of the vehicles or pieces of equipment to
be fueled by each pump.
(c) Fuel pumps must be located a minimum of seven feet from the edge of
the fueling pad.
(4) Drainage
(a) The paved area beneath the cover must be hydraulically isolated through
grading, berms, or drains. This will prevent uncontaminated stormwater
from running onto the area and carrying pollutants away.
(b) Drainage from the hydraulically isolated area must be directed to an
approved City sanitary sewer system, or authorized pretreatment facility.
(c) Surrounding runoff must be directed away from the hydraulically isolated
fueling pad to a stormwater destination that meet all stormwater
management practices of the Springfield Development code and other
applicable code requirements.
(5) Signage
(a) Signage must be provided at the fuel dispensing area and must be plainly
visible from all fueling activity areas.
(b) Signage must clearly specify the location of any applicable spill control
kits, shut-off valves, etc. and include all necessary instructions for their
use.
(6) Spill Control Manhole
(a) A spill control manhole must be installed on the discharge line of the
fueling pad (before the domestic waste line tie-in).
(b) The tee section must extend 18 inches below the outlet elevation, with an
additional 3 feet of dead storage volume below the tee to provide storage
for oil and grease.
(c) The total containment volume must be no less than 110% the volume of
the largest container or 10% of the total volume of product stored,
whichever is larger.
(d) The manhole must be located on private property.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 120 of 133
(7) Shut-Off Valves
(a) Shut-off valves are required to protect the City sewer systems or onsite
infiltration facilities of spill risks from chemicals and other constituents that
provide a danger for wide spread contamination, system damages or risk
to the public health. Manual shut-off valves must not be permitted unless
a request for an adjustment is approved by the City.
(b) Shut-off valves will be required in the following situations:
(i) Site or activity areas where corrosives or oxidizers are used or
stored (for example, concentrated acids are corrosives having a
pH of less than or equal to 5.0 and bases such as sodium or
ammonium hydroxide having a pH of greater than or equal to
12.0, common oxidizers are hydrogen peroxide and bleach); or
(ii) Substances which are water soluble or float on water; or
(iii) Solvents and petroleum products
(c) Traffic pathways that surround the fueling pad, also designated as high-
use/high-risk areas, will require a shut-off valve on the storm drainage
system.
(i) Valves installed on storm drainage systems must be installed
downstream of all private stormwater quality facilities to
accommodate spill containment.
(ii) These valves should be left open to facilitate stormwater flows
during normal conditions, and immediately closed in the event of a
spill.
(iii) The switch or handle to operate the shut-off valve must be clearly
marked and accessible, and identified on the signage at the fuel
dispensing area. In the event of a spill the valve must remain
closed until all spilled fuel and residue has been properly removed
and disposed of.
(d) Fueling pads will require a shut-off valve downstream of the spill control
manhole.
(i) Valves installed on sanitary sewer systems must be installed
before the domestic waste line tie-in.
(ii) These valves must automatically revert to the closed position.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 121 of 133
(iii) These valves must be kept closed, and opened only to allow
incidental drainage activities that do not pose to be a threat or risk
to the destination system.
(e) Shut-off valves must be located on private property and downstream of
the exposed area's collection system.
(i) All valves must be installed and maintained as per manufacturer's
recommendations. For more information about shut-off valves and
associated valve boxes, contact Building & Permit Services at
541-682-5086.
(8) Additional Requirements
(a) Installation, alteration, or removal of above-ground fuel tanks larger than
55 gallons, and any related equipment, are subject to additional
permitting requirements by the Springfield-Eugene Fire Marshal's Office.
For technical questions and permitting, call the Fire Marshal's Office
Permit Center at 541-682-5411, or visit them at Permit & Information
Center, 99 W. 10th Avenue, Eugene, OR 97401.
(b) Bulk fuel terminals, also known as tank farms, will require the following:
(i) Secondary containment equal to 110 percent of the product's
largest container or 10 percent of the total volume of product
stored, whichever is larger.
(i i) A separate containment area for all valves, pumps and coupling
areas with sub-bermed areas either in front of or inside the main
containment areas. These sub-bermed areas are required to have
rain shields and be directed to a City sanitary sewer destination
that meets all applicable code requirements if no City sanitary
sewer facility is available, drainage must be directed to a
temporary holding facility for proper disposal.
(iii) An impervious floor within all containment areas. Floors must be
sealed to prevent spills from contaminating the groundwater.
(iv) Truck loading and off-loading areas. These areas must follow
cover, pavement, drainage, spill control, and shut-off valve
requirements identified for fuel dispensing facilities.
(v) Shut-off valves installed for the drainage of the tank yard, must be
installed downstream of the drainage system of the primary
containment area, and kept closed. Valves installed for the
drainage of the truck pad and sub-bermed containment areas
must be installed on the sanitary sewer line downstream of the
spill control manhole.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 122 of 133
(vi) A batch discharge authorization before draining a containment
area. This authorization will determine appropriate disposal
methods, identify pretreatment requirements (if applicable), and
authorize the discharge. Pretreatment may be required for oil and
grease removal, and testing may be required to establish the
specific characteristics of the discharge.
(c) Underground fuel tanks less than 4,000 gallons in size are subject to
additional permitting requirements by Oregon's Department of
Environmental Quality (DEQ) and tanks larger than 4,000 gallons are
referred to the Federal Environmental Protection Agency (EPA). For
technical questions and permitting, call DEQ's NW Region main office at
1-800-844-8467 and ask for the Underground Storage Tank Permitting
Department.
(D) Above-ground Storage of Liquid Materials
(1) Above-Ground Storage of Liquid Materials include places where exterior storage
(either permanent or temporary) of liquid chemicals, food products, waste oils,
solvents, or petroleum products in above-ground containers, in quantities of 50
gallons or more exist.
(2) Containment
(a) Liquid materials must be stored and contained in such a manner that if
the container(s) is ruptured, the contents will not discharge, flow, or be
washed into a receiving system.
(b) A containment device and/or structure for accidental spills must have
enough capacity to capture a minimum of 110 percent of the product's
largest container or 10 percent of the total volume of product stored,
whichever is larger. Containers, such as double-walled containers, with
internal protection are considered to meet this requirement.
(3) Cover
(a) Storage containers (other than tanks) must be completely covered to
prevent stormwater contact. Runoff must be directed from the cover to a
stormwater destination that meets all applicable code requirements.
(b) Covers 10 feet high or less must have a minimum overhang of 3 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated activity area.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 123 of 133
(c) Covers higher than 10 feet must have a minimum overhang of 5 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated activity area.
(2) Pavement
(a) All above ground storage of liquid material must occur in paved areas.
The storage area must be paved with asphalt or concrete and must meet
all applicable building code requirements. Sizing of the paved areas must
be adequate to cover the area intended for storage.
(3) Drainage
(a) All paved storage areas must be hydraulically isolated through grading,
berms, or drains to prevent uncontaminated stormwater run-on to a
storage area.
(b) Covered storage areas:
(i) Significant amounts of precipitation are not expected to
accumulate in covered storage areas, and drainage facilities are
not required for the contained area beneath the cover.
(i i) If the applicant elects to install drainage facilities, the drainage
from the hydraulically isolated area must be directed to a sanitary
sewer destination that meets all applicable code criteria.
(c) Uncovered storage areas with containment:
(i) Water will accumulate in uncovered storage areas during and after
rain. Any contaminated water cannot simply be drained from the
area. It must be collected, inspected, and tested at the expense of
the property owner before proper disposal can be determined.
(i i) Some type of monitoring may also be needed to determine the
characteristics and level of contamination of the stormwater.
(d) All discharges to the sanitary sewer system must be considered batch
discharges and must require approval and meet applicable code
requirements.
(i) Pretreatment requirements must be set as part of the discharge
approval process, based on the types and quantities of material to
be discharged.
(i i) A discharge evaluation must be performed before connection to a
sanitary sewer facility.
(iii) Testing may be required to establish characteristics of the sanitary
sewer or contaminated stormwater and to verify that local
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 124 of 133
discharge limits are not exceeded. MWMC illicit discharge staff
can be contacted to start this process.
(4) Signage
(a) Signage must be provided at the liquid storage area and must be plainly
visible from all surrounding activity areas.
(E) Solid Waste Storage
(1) Solid Waste Storage Areas, Containers, and Trash Compactors include outdoor
areas with one or more facilities that store solid waste (both food and non-food
waste) containers.
(a) One- and two-family residential solid waste storage areas, containers,
and trash compactors are exempt from this code subsection.
(b) Solid waste includes both food and non-food waste or recycling. Solid
waste containers include compactors, dumpsters, compost bins, grease
bins, recycling areas, and garbage cans.
(c) Debris collection areas used only for the storage of wood pallets or
cardboard is excluded from these requirements.
(d) The following site uses and activities include all commercial and industrial
development with facilities that store solid wastes, both food and non-
food.
(i) Outdoor solid waste storage areas.
(ii) Multi-family residential sites if a shared trash collection area is
proposed.
(iii) Activity areas used to collect and store refuse or recyclable
materials, such as can or bottle return stations and debris
collection areas.
(iv) Facilities whose business is to process and/or recycle wood
pallets or cardboard.
(2) Design
(a) For approval of solid waste storage and handling activity areas in the City
of Springfield, the following design requirements will apply. See below for
a clarification of each requirement:
Activity/Use I Requirements
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 125 of 133
Cover Pavement Hydraulicly Sanitary
Isolated Sewer
Drain
Multi Residential X X X X
(with shared trash
areas
Commercial X X X X
Industrial X X X X
Compactors X X X X
(regardless of use
Can and Bottle X X X X
Return Stations
(3) Cover
(a) A permanent canopy, roof, or awning must be provided to cover the solid
waste storage activity area and must be constructed to cover the activity
area so rainfall cannot come in contact with the waste materials being
stored. The cover must be sized relative to the perimeter of the
hydraulically isolated activity area it is to cover. Runoff must be directed
from the cover to a stormwater destination that meets all applicable code
requirements.
(F) Outdoor Storage of Bulk Materials
Any bulk materials storage location that is not completely enclosed by a roof and
sidewalls is an outdoor storage area.
(1) Bulk Materials Categories
(a) Bulk materials are separated into three categories based on risk
assessments for each material stored: high-risk, low-risk, and exempt.
High-Risk Materials Low-Risk Materials Exempt Materials
• Recycling materials with • Recycling materials • Washed gravel/rock
potential effluent without potential effluent • Finished lumber
• Corrosive materials (e.g. • Scrap or salvage • Plastic products
lead-acid batteries) goods (hoses, gaskets, pipe,
• Storage and processing • Metal etc.)
of • Sawdust/bark chips • Clean concrete
food items • Sand/dirt/soil products (blocks,
• Chalk/gypsum products (including pipe, etc.)
• Feedstock/grain contaminated soil piles) • Glass products (new,
• Material by-products • Material by-products non-recycled)
with without potential effluent
potential effluent • Unwashed gravel/rock
• Asphalt • Composting
• Fertilizer Operations
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 126 of 133
• Pesticides
• Lime/lye/soda ash
• Animal/human wastes
• Treated Lumber
(2) Cover
(a) Low-risk materials must be covered with a temporary plastic film or
sheeting at a minimum.
(b) High-risk materials are required to be permanently covered with a canopy
or roof to prevent stormwater contact and minimize the quantity of rainfall
entering the storage area. Runoff must be directed from the cover to a
stormwater destination that meets all applicable code requirements.
(c) Covers 10 feet high or less must have a minimum overhang of 3 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated activity area.
(d) Covers higher than 10 feet must have a minimum overhang of 5 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated activity area.
(3) Pavement
(a) Low-risk and exempt material storage areas are not required to be paved.
(b) High-risk material storage areas must be paved beneath the structural
cover.
(4) Drainage
(a) Low-risk material storage areas are allowed in areas served by standard
stormwater management systems. However, all erodible materials being
stored must be protected from rainfall.
(b) If materials are erodible, a structural containment barrier must be placed
on at least three sides of every stockpile to act as a barrier to prevent
uncontaminated stormwater from running onto the storage area and
carrying pollutants away.
(i) If the area under the stockpile is paved, the barrier can be
constructed of asphalt berms, concrete curbing, or retaining walls.
(ii) If the area under the stockpile is unpaved, sunken retaining walls
can be used. The applicant must clearly identify the method of
containment on the building plans.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 127 of 133
(c) For high-risk material storage areas, the paved area beneath the
structural cover must be hydraulically isolated through grading, structural
containment berms or walls, or perimeter drains to prevent runoff.
(i) Significant amounts of precipitation are not expected to
accumulate in covered storage areas, and drainage facilities are
not required for the containment area beneath the cover.
(ii) If the applicant elects to install drainage facilities, the drainage
from the hydraulically isolated area must be directed to the City's
sanitary sewer (with approval from the MWMC Illicit discharge
division) and must meet all applicable code criteria.
(5) Additional Requirements
(a) Storage of pesticides and fertilizers may need to comply with specific
regulations outlined by the Oregon Department of Environmental Quality
(DEQ). For answers to technical questions, call DEQ's NW Region main
office at 1-800-844-8467.
(b) A sampling manhole or other suitable stormwater monitoring access point
may be required to monitor stormwater runoff from the storage area. This
may apply to certain types of storage activities and materials or if an
alternative source control is proposed. This requirement complies with
Springfield Development Code 4.3.110D, which requires discharge to be
treated. PW staff will review for applicability of this requirement.
(c) Signage must be provided at the storage area if hazardous materials or
other materials of concern are stored. Signage must be located so it is
plainly visible from all storage activity areas. More than one sign may be
needed to accommodate large storage areas.
(d) If the applicant elects to install drainage facilities to the City's sanitary
sewer system, a shut-off valve must be required for the structurally
covered storage area.
(6) Alternative Protection Measures
(a) In lieu of covering mineral resource mining, recovery, stockpiling, and
processing operations and low-risk material storage areas receiving land
use approval, the applicant may propose alternative protection measures
that demonstrate that stormwater runoff from the site will not contaminate
adjoining properties, surface waters, and ground water as part of their
land use application.
(G) Material Transfer Areas/Loading Docs
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 128 of 133
(1) Material Transfer Areas/Loading Docks include areas that are either interior or
exterior to a building, designed to accommodate a commercial truck/trailer being
backed up to or into them, and used specifically to receive or distribute materials
to and/or from commercial trucks/trailers. Includes loading/unloading facilities
with docks, and large bay doors without docks.
(a) These requirements also apply to all development proposing the
installation of new material transfer areas or structural alterations to
existing material transfer areas (e.g., access ramp regrading, leveler
installations) with the following characteristics:
(i) The area is designed (size, width, etc.) to accommodate a
commercial truck (1 ton and larger) or trailer being backed up to or
into it; and
(ii) The area is designed so that it can be used to receive or distribute
materials to and from trucks or trailers from any side.
(b) Two standard types of material transfer areas associated with buildings
are:
(i) Loading/unloading facilities with docks
(ii) Large bay doors without docks
(c) The requirements in this section do not apply to material transfer areas or
loading docks used only for mid-sized to small-sized passenger vehicles
and areas restricted by lease agreements or other regulatory
requirements to storing, transporting or using materials that are classified
as domestic use, for example, primary educational facilities (elementary,
middle or high schools), or buildings used for temporary storage, and
churches.
(2) Cover
(a) The hydraulically isolated areas in front of loading docks are required to
be permanently covered with a canopy or roof to prevent stormwater
contact and to minimize the quantity of rainfall entering the loading dock
area. Runoff must be directed from the cover to a stormwater destination
that meets all applicable code requirements.
(b) Covers 10 feet high or less must have a minimum overhang of 3 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated activity area.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 129 of 133
(c) Covers higher than 10 feet must have a minimum overhang of 5 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated activity area.
(3) Pavement
(a) A paved material transfer area must be placed underneath and around
the loading and unloading activity area with asphalt or concrete that
meets all applicable building code requirements. This will reduce the
potential for soil contamination with potential impacts on groundwater and
will help control any acute or chronic release of materials present in these
areas.
(4) Drainage
(a) Loading Docks:
(i) Drainage from the hydraulically isolated area must be directed to a
sanitary sewer that meets all applicable code requirements.
Surrounding runoff and drainage from the access ramp must be
directed away from the hydraulically isolated area to a stormwater
destination that meets all applicable requirements of the
Springfield Development Code.
(ii) The requirement for the drainage from the hydraulically isolated
area of the loading dock to be directed to the City's sanitary
sewer, or authorized pretreatment facility may be waived if PW
determines there is no gravity sanitary sewer service available
and an appropriately sized, underground temporary storage
structure (such as a catch basin with no outlet or dead-end sump)
is provided.
(5) Non-Gravity Option
(a) Activity areas that cannot achieve gravity sanitary sewer service may be
allowed to install a pressurized (pumped) system. These types of
installations will require the following to be provided at the time of building
permit application:
(i) Proof that gravity sanitary sewer service cannot be obtained; and
(ii) Details of an electronic sump pump system equipped with a float
switch
(b) Pressurized system installations are considered "permanent equipment"
and deemed the property owner's liability in the event of system failure or
if the property becomes vacated.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 130 of 133
(c) The Building & Permit Services will review all sump pump or sewage
ejector installations for compliance with Uniform Plumbing Code and
Oregon State Plumbing Specialty Code.
(d) Bay Doors and Other Interior Transfer Areas: Because interior material
transfer areas are not expected to accumulate precipitation, installation of
floor drains is not required or recommended. It is preferable to handle
these areas with a dry-mop or absorbent material. If interior floor drains
are installed, they must be plumbed to the City's sanitary sewer facility or
authorized pretreatment facility. Interior transfer areas may not be sloped
to drain to the exterior of the building.
(e) Bay doors and other interior transfer areas must be designed so that
stormwater runoff does not enter the building. This can be accomplished
by grading or drains. Interior surfaces may not drain or be washed down
to the exterior of the building.
(6) Signage
(a) Signage must be provided at the material transfer area and must be
plainly visible from all surrounding activity areas.
(5) Additional Requirements
(a) Bay doors and other interior transfer areas must provide a 10-foot "no
obstruction zone" beyond the entrance within the building. This will allow
the transfer of materials to occur with the truck or trailer end placed at
least 5 feet inside the building, with an additional staging area of 5 feet
beyond that. The "no obstruction" zone must be clearly identified on the
stormwater management plan and on the building plan at the time of the
building permit application. The area must be identified at the facility by
painting the "no obstruction zone" with bright or fluorescent floor paint.
(b) Shut-off valves will be required under the following situations:
(i) Site activity areas that are exposed to corrosives or oxidizers that
can harm conveyance system components (such as battery acid).
(ii) Substances that do not settle or remain in one location, but are
capable of being dissolved in or float on top of water (such as oil
and grease). These substances can spread rapidly into
downstream systems, causing widespread impacts and difficult
clean-up situations.
(iii) Substances that are known to infiltrate through soils and
contaminate groundwater.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 131 of 133
(c) Valves located in material transfer areas are typically left open to facilitate
drainage during normal conditions, and immediately closed in the event of
a spill.
(d) Prior to transfer activities of harmful substances, the valves should be
closed and only re-opened after the transfer is complete. The shut-off
valves must be located on private property and downstream of the
exposed area's collection system.
(H) Equipment and/or Vehicle Washing Facilities
(1) Equipment and/or Vehicle Washing Facilities include designated equipment
and/or vehicle washing or steam cleaning areas, including smaller activity areas
such as wheel washing stations.
(2) Cover
(a) The washing area must be covered with a permanent canopy or roof so
precipitation cannot come in contact with the washing activity area.
Precipitation must be directed from the cover to a stormwater destination
that meets all applicable code requirements.
(b) Covers 10 feet high or less must have a minimum overhang of 3 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated washing activity area it is to cover.
(c) Covers higher than 10 feet must have a minimum overhang of 5 feet on
each side. The overhang must be measured relative to the perimeter of
the hydraulically isolated washing activity area it is to cover.
(3) Pavement
(a) A paved wash pad must be placed under and around the washing activity
area with asphalt or concrete that meets all applicable building code
requirements. Sizing of the paved area must adequately cover the activity
area, including the placement of the vehicle or piece of equipment to be
cleaned.
(4) Drainage
(a) The paved area beneath the cover must be hydraulically isolated through
grading, berms, or drains to prevent uncontaminated stormwater from
running onto the area and carrying pollutants away.
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 132 of 133
(b) Drainage from the hydraulically isolated area must be directed to the
City's sanitary sewer, or authorized pretreatment facility.
(c) Surrounding runoff must be directed away from the hydraulically isolated
washing pad to a stormwater destination that meets all applicable
requirements of the Springfield Development Code.
(5) Oil Control
(a) All vehicle and equipment washing activities will be reviewed for needed
oil controls to comply with the City's adopted plumbing code and
Metropolitan Wastewater Management Commission requirements for
pretreatment.
(b) The following design criteria are established for oil/water separators
discharging to a sanitary sewer facility:
(i) Washing Areas Protected with a Cover or Located Inside a
Structure:
Baffled oil/water separators and spill control (SC-Type) separators
must not be allowed for use with equipment and/or vehicle
washing applications.
Note: activities and processes of a washing facility change over
time and the introduction of heat and surfactants may occur.
(ii) Coalescing plate separators must be designed to achieve 100
ppm non-polar oil and grease in the effluent from the peak flow
generated by the washing activity. Testing information must be
submitted by the manufacturer of the unit that supports the 100
ppm effluent standard at the calculated flow rate. Standard flow
from a 5/8" hose is estimated to be 10 gpm. For specially
designed washing units, check the vendor specifications for
maximum flow rates.
(iii) Any pumping devices must be installed downstream of the
separator to prevent oil emulsification.
(iv) Separator details must be shown on the building plans submitted
for permit, and must match manufacturer specifications and
details, including the unit flow rate, effluent water quality, and
maximum process flow rate.
(c) On-site Wash Recycling Systems Wash may be used for oil control as
long as they can meet effluent discharge limits for the City's sanitary
sewer system. A detail of the wash recycling system and vendor
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit A Page 133 of 133
specifications identifying effluent efficiencies must be submitted as part of
the building plans at the time of building permit application.
(1) Covered Vehicle Parking Structures
(1) Covered Vehicle Parking Structures include enclosed buildings, not including
single-level covers such as canopies, overhangs, and carports, used to cover
parked vehicles.
(2) Drainage
(a) Stormwater runoff from the top floor of a multi-level parking structure must
be directed to a stormwater destination that meets all water quality
requirements of the Springfield Development Code and any other
applicable code requirements.
(b) Drainage from lower floor of a multi-level parking structure is not expected
to accumulate significant amounts of precipitation runoff and drainage
facilities are not required for the lower floors.
(c) If the applicant elects to install drainage facilities, the drainage from the
lower floors must be directed to the sanitary sewer.
(3) Adjacent, Uncovered Portions of the Site
(a) The surrounding uncovered portions of the site must be designed so
stormwater does not enter the covered parking areas. This can be
accomplished through grading, drains, or exterior walls
Appendix H—Explanation of Appendices to the Development Code
Stormwater Post-Construction Requirements Update
Ordinance No. 6464
Exhibit B, Page 1 of 19
STAFF REPORT and FINDINGS OF FACT
TYPE IV— LEGISLATIVE AMENDMENT TO THE SPRINGFIELD DEVELOPMENT CODE
SPRINGFIELD CASE NUMBER: 811-23-000124-TYP4
PLANNING COMMISSIONS' HEARING DATE: August 1, 2023, continued to September 5, 2023
ELECTED OFFICIALS' HEARING DATE: November 6, 2023
REPORT DATE: September 20, 2023, revised November 9, 2023
PROJECT NAME: Stormwater Post-Construction Requirements Code Amendments
AFFECTED AREA: All properties within the City of Springfield urban growth boundary
I. NATURE OF THE REQUEST
The City of Springfield seeks approval of amendments to the Springfield Development Code for
consistency with the City's Municipal Separate Storm Sewer System (MS4) Permit.The purpose
of the Post-Construction Requirements Update project is to modify the Springfield Development
Code to comply with the Oregon Department Environmental Quality's (DEQ) requirements of
the City. Updating Springfield's Development Code to align with current state requirements will
allow the City to continue to participate in the MS4 permit program.
II. BACKGROUND
In accordance with the 1972 Federal Clean Water Act,the Oregon Department of Environmental
Quality(DEQ) issued a permit to the City of Springfield called a Municipal Separate Storm Sewer
System (MS4) permit.The permit regulates pollution from stormwater released to surface
water, including the McKenzie and Willamette Rivers. The current MS4 permit characterizes
Springfield's stormwater drainage system, establishes goals, policies and implementation
actions; and measures, reports, and adaptively manages the City's water resources and
stormwater runoff.The permit and Springfield Development Code implement and enforce post-
construction site runoff controls within the Springfield urban growth boundary, including
unannexed areas through an intergovernmental agreement with Lane County. The post-
construction site runoff control program reduces discharge of pollutants and addresses
stormwater runoff from new development and redevelopment.
Regulations for post-construction stormwater runoff are contained in the Springfield
Development Code and the Engineering Design Standards and Procedures Manual (or
EDSPM). Amendments to the Springfield Development Code are subject to a land use approval
process that includes public hearings, recommendations from the Planning Commissions, and
final co-adoption by the elected officials.The amendments to the EDSPM do not require a land
use process and will be adopted directly by the City Council without a Planning Commission
recommendation. Information from the City's EDSPM will be shared at the meeting as portions
of the manual are proposed for adoption into the Code.
The purpose of the MS4 Post-Construction Runoff Amendment Project is to update the
Springfield Development Code to comply with Oregon DEQ's requirements of the City, including
requirements to regulate post-construction site runoff and minimize barriers to low impact
development and green infrastructure under the City's MS4 Permit. These amendments would
allow and encourage the use of stormwater treatment facilities including swales, rain gardens,
and pervious pavements and strengthen requirements that address stormwater quality issues
and improve the quality of water in the City's drinking water protection areas.
Staff Report and Findings of Fact Page 1 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 2 of 19
The project objectives are to:
1) Review and update enforceable post-construction stormwater management requirements
in ordinance or other regulatory mechanism that includes a site performance standard and
alternative treatment standard.
2) Review and update post-construction requirements for development and redevelopment,
especially for project sites that create or replace 5,000 square feet or more of impervious
area.
3) Review development code and remove barriers to low impact development and green
infrastructure.
III. SITE INFORMATION
The amendments are not site-specific, they apply to a large area and a large number of
properties. Affected properties are those with project sites that discharge stormwater to the
storm sewer system that create or replace 5,000 square feet or more of impervious surface area
or for development projects that disturb one or more acres of land. Runoff from these
developments must be captured by structural stormwater controls which are physically
designed, installed, and maintained facilities that prevent or reduce the discharge of pollutants
to minimize the impacts on waterbodies.
IV. PROCEDURAL REQUIREMENTS AND CITIZEN INVOLVEMENT
Under SDC 5.6.110, amendments of the Development Code text are reviewed under a Type 4
procedure as a legislative action. Type 4 procedures, as defined in SDC 5.1.600, require a review
and recommendation by the Planning Commission and adoption of ordinance by City Council.
The code updates include changes that apply within the urbanizable areas that are between the
City limits and the Springfield urban growth boundary.Therefore,the code updates are subject
to provisions of the City of Springfield and Lane County's urban transition agreement, which
requires the City and County to jointly develop land use regulations to be applied to the
urbanizable portion of the Springfield UGB. The Springfield Planning Commission and Lane
County Planning Commission held a joint public hearing for the purpose of developing their
recommendations to City Council and Board of Commissioners, respectively. The City Council
and Board of County Commissioners will hold a joint public hearing to co-adopt the regulations
applicable to the urbanizable area.The Director for the City of Springfield initiated these
development code amendments as is allowed under SDC 5.6.105(B).
In accordance with the City of Springfield Citizen Involvement Program,the Committee for
Citizen Involvement (CCI) reviewed and approved a Citizen Involvement Strategy for this
proposal on April 18, 2023. Per this strategy and other requirements the City has completed the
following:
• In April 2023, created a project page on Springfield Oregon Speaks with links to the
Development Code Updates webpage on the City of Springfield website.The webpages
provided opportunities for the public to view key messages or relevant resources and
factsheets and collect input from the public.
• Held two public workshops to convey the main points of the project to development
professionals, on June 13 and June 15, 2023.
Staff Report and Findings of Fact Page 2 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 3 of 19
• Emailed notice of the proposed amendments to stakeholder groups per the Citizen
Involvement Strategy on June 23, 2023.
• As required by SDC 5.1.615(E), provided agency referrals to the Development Review
Committee regarding the proposed amendments via email on June 23, 2021.
• Submitted notice of the proposed amendments to the Department of Land
Conservation and Development (DLCD) on June 26, 2023, 35 days in advance of the first
evidentiary hearing as required by ORS 197.610(1) and OAR 660-018-0020.
• Mailed notice of the Planning Commission Joint Hearing on July 6, 2023 to development
professionals (developers, builders, landscape architects, engineers, and realtors,
including the Springfield Board of Realtors and Lane County Home Builders Association)
and environmental groups who expressed an interest in being notified of future code
amendments (following the 2022 Development Code Update Project).
• Emailed notice of the proposed amendments to stakeholder groups per the Citizen
Involvement Strategy on June 23, 2023.
• As required by SDC 5.1.615(E), provided agency referrals to the Development Review
Committee regarding the proposed amendments via email on June 23, 2021.
• Published notice of the proposed amendments in The Chronicle on July 6, 2023 as
required by SDC 5.1.615.
• Posted notice of the proposed amendments and the dates of the Planning Commissions'
public hearings on the City of Springfield website which routinely posts public hearing
notices.
• An amendment to the proposed code would prohibit stormwater infiltration and affect
property setbacks, which triggered "Ballot Measure 56" notice under ORS 227.186. As
this code revision was not initially included in the draft amendments staff did not
provide said notice prior to the August 1 public hearing. Staff mailed notice pursuant to
ORS 227.186 on August 11, at least 21 days prior to the continued hearing date of
September 5, 2023.
• Published notice of the Elected Officials' public hearing in the Chronicle on October 12,
2023 as required by SDC 5.1.615(A).
As of the date of this staff report, there were inquiries about the proposed code language. Staff
received one written comment from Staff at the Long Tom Watershed Council and one written
comment from Mike Koivula in response to the information in the notices.
• There are a number of reasons why it makes sense to align with the City of Eugene's
stormwater manual, but Eugene's manual is nearly a decade old and does not reflect
current best practices. Eugene is aware of this and is in the process of updating their
manual to address the latest science, inconstancies, and other shortfalls.As such, it does
not seem to be in Springfield's best interest to adopt a manual that is known to be out of
date, especially at it relates to facility design. Known best practices are to have a
functional sediment drop at all inlets, to have no fabric, and to limit gravel galleries and
associated underdrains to the lowest third of the facility. Good examples of typical
details that incorporate these concepts and more can be found in Portland's stormwater
manual. Depth of soil, soil types, and how newly imported soil interfaces with existing
soils should also be updated to best practices. Typically, new soil should be tilled to a min
depth of 6"with a min. of 18"of new stormwater specific soil added. This soil should be
high in organics and incorporate biochar at a minimum of 4%by volume to best manage
Staff Report and Findings of Fact Page 3 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 4 of 19
the urban complex of pollutants and to maximize detention and infiltration. 1 am happy
to discuss these recommendations further, and point you to scientific articles that
support these recommendations if that is desired.—Sarah Whitney
Staff Response: Staff appreciate the Long Tom Watershed Council for providing feedback on the
Stormwater Post-Construction Requirements Update and acknowledge that some of the
proposed practices are pragmatic, including changing the standard facility design details or
requirements of some items (the depth of soil and soil types). While some of the proposed
details in the Eugene manual may be out of date, Springfield is aligning with the currently
adopted regional standards,which are well established and are what can reasonably be built by
most developers. Sourcing exotic materials like biochar may be unrealistic in many Low Impact
Development or vegetated structural stormwater control facilities. For instance, biochars have
been reported to improve plant health through providing improved water, nutrient retention,
drainage and aeration; but they can also produce high pH which can reduce soil acidity levels
and negatively impact soil microbes causing a detrimental effect to certain plants. Furthermore,
many studies refer to relatively limited experimental assessments and report on quite specific
plant, soil, and environmental interactions. Therefore, more research is recommended before
including biochars in a typical stormwater facility design.Amendments to the Springfield
Development Code include the addition of Appendix D Typical Stormwater Facility Details which
was brought over from the Springfield Engineering Manual (EDSPM). One such amendment, is
the requirement of a minimum 24-inch growing medium with at least 50%organic material in
the Drinking Water Protection 0-2 Year Time of Travel Zone,which can accomplish nearly the
same soil composition traits as the installation of biochars. Finally, Staff will consider amending
these standards when regional stormwater codes at the City of Eugene and Lane County are
amended and codified.
• 2 ideas. 1 question if sfr should be allowed to dispose of storm water in a drywell.A
convenient drywell open to access, will likely be used by residents to dispose of many
products that could damage ground water, oil,pesticides, paint, etc. Consider a program
to encourage use of non toxic moss control products. Most of the zinc moss killers are
toxic to fish and amphibians, and do not reliably break down. Sodium percarbonate is a
very effective moss killer and destroys preemergent moss spores yet breaks down fairly
quickly to completely benign compounds.A treatment is not expensive and lasts for a
long time. Thank you to Planning Commissioners for your service to Springfield residents.
-Mike Koivula
Staff Response:The City has some tools and programs that address the concerns that are not
currently regulated through the Springfield Development Code:
• First, Springfield does not allow open drywells.They must be covered so that the only
entrance is the pipe carrying the water.The most frequently used type of drywell is a
soakage trench which does not have any openings above ground except for the pipe that
connects to the roof drains and typical installation does not having an easy entry point to
dispose of liquids. Therefore, frequent use of drywells for residential use is not a concern at
this time. Furthermore, Springfield Municipal Code 4.370-4.372 prohibits illicit discharges
into the City stormwater system. This prohibition applies to over-use or misuse of products
like moss killer in a residential area if it is posing a threat to the water quality of the city's
storm system. If there was an open stormwater facility, it also applies to using that facility
Staff Report and Findings of Fact Page 4 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 5 of 19
as a dump/to dispose of items. The Environmental Services Department staff do take
enforcement action when they become aware that someone is discharging substances into a
stormwater facility that are not stormwater.
• Second,the MS4 permit also requires the City to provide education and outreach related to
water quality. The Environmental Services Department"Stream Team" provides
information to Springfield residents through their SUB bills several times a year and with the
help of Eugene and Lane County, are actively working on a handout for moss control best
practices specifically for Springfield.The handout and future outreach campaign will be
based on resources from regional municipalities and the Northwest Center for Alternatives
to Pesticides.
For this request,the Springfield and Lane County Planning Commission shall make a
recommendations respectively to the Springfield City Council and Lane County Board of
Commissioners which are the Approval Authorities for the final local decision. Per the Urban
Transition Intergovernmental Agreement and SDC 5.1.625, development code amendments
which impact areas outside the City limits must be co-adopted by the Lane County Board of
Commissioners in order to apply to urbanizable areas within the Springfield UGB. Decisions of
the Springfield City Council and Lane County Board of Commissioners may be appealed to the
Oregon Land Use Board of Appeals within 21 calendar days of the date the decision becomes
final as specified in ORS 197.830(SDC 5.1.630(F)).
V. APPROVAL CRITERIA&FINDINGS
The request is subject to approval criteria in SDC 5.6.115, which covers adoption or amendment
of refinement plans, plan districts and the development code.The following approval criteria
are listed under SDC 5.6.115:
A. In reaching a decision on the adoption or amendment of refinement plans and this Code's
text, the City Council shall adopt findings that demonstrate conformance to the following:
1. The Metro Plan and Springfield Comprehensive Plan;
2. Applicable State statutes;and
3. Applicable State-wide Planning Goals and Administrative Rules.
Findings showing that the amendments to the development code meet the applicable criteria of
approval appear in regular text below. Direct citations or summaries of criteria appear in italics
and precede or are contained within the relevant findings.
Conformance with the Metro Plan and Springfield Comprehensive Plan
The adopted Metro Plan and Springfield Comprehensive Plan are the acknowledged long-range
plans that provide the board framework for land use planning within the City of Springfield.The
policies of the Springfield Comprehensive Plan —Residential Land Use and Housing Element are
intended to refine and update (as opposed to replace)the goals, objectives and policies of the
Metro Plan's Residential Land Use and Housing Element.The Springfield Comprehensive Plan—
Economic and Urbanization Elements replace the applicable sections of the Metro Plan
pertaining to employment lands and urbanizable lands.
Staff Report and Findings of Fact Page 5 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 6 of 19
The Metro Plan and Springfield Comprehensive Plan contain topics or"elements". Each element
contains a goal and policies that will guide Springfield's growth and development through the
2010-2030 planning period.
The Stormwater Post-Construction Requirements Update project is consistent with the following
Metro Plan policies:
Environmental Resources Element
Air, Water and Land Resources Quality(Goal 6)
C.25 Springfield, Lane County, and Eugene shall consider downstream impacts when planning
for urbanization,flood control, urban storm runoff, recreation, and water quality along
the Willamette and McKenzie Rivers.
Finding 1: The amended standards in SDC 4.3.110 Stormwater Management require the City of
Springfield to review all permit applications to determine if development is proposed to:
1) Create or replace 5,000 square feet or more of impervious surface area and discharge to the
storm system;
2) Disturb one or more acres of land within the development area; and
3) Generate peak flows in excess of 0.5 cubic feet per second within the development area.
If an application does meet these standards,then the City requires developers to incorporate
one or more structural stormwater controls.
Finding 2: Structural stormwater controls are physically designed, installed, and
maintained to prevent or reduce the discharge of pollutants in stormwater to minimize the
impacts of stormwater on water bodies. Examples of structural stormwater controls or Best
Management Practices(BMPs) include: (1) storage practices such as wet ponds and extended
detention outlet structures; (2)filtration practices such as grassed swales, sand filters and filter
strips; and (3) filtration practices such as filtration basins and infiltration trenches.
Finding 3: The standards require that applicants capture the first one and four tenths
inches (1.4") of rainfall from each storm event and route them to one or more structural
stormwater controls (referred to as the Site Performance Standard) or if that standard cannot
be met, rainfall must be retained onsite to the maximum extent practicable and the remainder
of the runoff up to 1.4" must be treated to remove at least 80%of Total Suspended Solids(TSS)
(referred to as the Treatment Standard).
Finding 4: Furthermore, per the amended code,the City will require applicants to submit a
Stormwater Study to describe how the proposed stormwater management approach targets the
natural surface or predevelopment hydrologic function of the area through the installation of a
structural stormwater control. It must also address the facilities impact on offsite flows,
drainage areas, environmentally sensitive areas,flood elevations or flood ways, and their
proximity to natural resource areas. By requiring a stormwater study for all structural
stormwater controls that are installed to offset the impacts of impervious surface development,
the City of Springfield considers the downstream impact of urbanization,flood control,
stormwater runoff, recreation, and water quality along the McKenzie and Willamette Rivers.
Staff Report and Findings of Fact Page 6 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 7 of 19
C.266 Local governments shall continue to monitor, to plan for, and to enforce applicable air
and water quality standards and shall cooperate in meeting applicable federal,state,
and local air and water quality standards.
Finding 5: These amendments are required for the City to comply with its MS4 Permit,
pursuant to Oregon Revised Statute (ORS)468B. 050 and Section 402 of the Federal Clean Water
Act.This Metro Plan policy is further addressed in response to Statewide Planning Goal 6. See
Finding 30 below.
Natural Hazards(Goal 7)
C.32 Local governments shall require site-specific soil surveys and geologic studies where
potential problems exist. When problems are identified, local governments shall require
special design considerations and construction measures be taken to offset the soil and
geologic constraints present, to protect life and property, public investments, and
environmentally-sensitive areas.
Finding 6: The City's MS4 permit requires the City to require structural stormwater
controls for new development and redevelopment project that create or replace 5,000 square
feet or more of impervious surface area or disturb one or more acres of land. As discussed
above, applicants must capture the first one and four tenths inches (1.4") of rainfall from each
storm event and route them to one or more structural stormwater controls. If that standard
cannot be met due to technical infeasibility or site constraints, applicants can apply for review
under the alternative Treatment Standard. Under the Treatment Standard, rainfall must be
retained onsite to the maximum extent practicable and the remainder of the 1.4" of runoff must
remove at least 80%of Total Suspended Solids from any storm event.The alternative Treatment
Standard provides "special design consideration" for sites that may not be able to capture the
Site Performance Standard of 1.4" rainfall due to: shallow bedrock, high groundwater,
protection of groundwater from contamination, soil instability as documented by geotechnical
analysis, land use that is inconsistent with the capture and infiltration of stormwater,the known
presence of soil contamination, or constraints arising from the Drinking Water Protection
Overlay District. Therefore, where an application proposes development on a property with site
constraints, an applicant must take measures to offset the soil and geologic constraints present
to protect life, property, public investments, and environmentally-sensitive areas.
Environmental Design Element
E.2 Natural vegetation, natural water features, and drainage-ways shall be protected and
retained to the maximum extent practical. Landscaping shall be utilized to enhance
those natural features. This policy does not preclude increasing their conveyance
capacity in an environmentally responsible manner.
Finding 7: The development code amendments have clear allowances for the use of
vegetated stormwater treatment. Structural stormwater controls should primarily include
vegetation with mechanical treatment used as a last resort.The vegetation may also count as
part of the required site landscaping. Therefore,the use of vegetated structural stormwater
controls or Low Impact Development may form the basis of natural vegetation areas or in
Staff Report and Findings of Fact Page 7 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 8 of 19
required setbacks along natural water features and will capture and retain runoff before they
impact drainage-ways to protect them to the maximum extent practical.
E.3 The planting of street trees shall be strongly encouraged, especially for all new
developments and redeveloping areas(where feasible)and new streets and
reconstruction of major arterials within the UGB.
Finding 8: The amendments are in conformance with the above stated policy as the City of
Springfield maintains a list of approved street trees.The City's plant and tree lists have been
updated and reformatted to be clearer and easier to use. During draft review, staff contacted
local arborists and landscape architects to receive feedback on the City's Facility Plant and Street
Tree lists.The lists have been amended to include criteria for approval of species not currently
on the list and to be consistent with Eugene's 2014 Stormwater Management Manual Facility
Planting Design. Non-native invasive species are not allowed in stormwater facilities and only
natives are allowed in stormwater facilities within Natural Resource Protection Area setbacks. A
minimum of three unique species are required per facility for species diversity.
E.4 Public and private facilities shall be designed and located in a manner that preserves and
enhances desirable features of local and neighborhood areas and promotes their sense
of identity.
Finding 9: The amendments require developers to design structural stormwater
control facilities based on their ability to prevent or reduce the discharge of pollutants in
stormwater on waterbodies. Examples of structural stormwater controls include:wet ponds
and extended detention outlet structures, grassed swales, sand filters and filter strips, and
filtration basins and infiltration trenches. By prioritizing management practices that mimic
natural surface or predevelopment hydrological functions and the use of Low Impact
Development approaches or green infrastructure, the City is actively working to preserve and
enhance local neighborhood areas and promote their sense of identity through the installation
of these facilities.
The Stormwater Post-Construction Requirements Update project is consistent with the following
Public Facilities and Services Element policies:
Services to Development Within the Urban Growth Boundary:Stormwater
G.13 Improve surface and ground water quality and quantity in the metropolitan area by
developing regulations or instituting programs for stormwater to:
a. Increase public awareness of techniques and practices private individuals can
employ to help correct water quality and quantity problems;
b. Improve management of industrial and commercial operations to reduce negative
water quality and quantity impacts;
c. Regulate site planning for new development and construction to better manage pre-
and post-construction storm runoff, including erosion, velocity, pollutant loading,
and drainage;
d. Increase storage and retention and natural filtration of storm runoff to lower and
delay peak storm flows to settle out pollutants prior to discharge into waterways,
Staff Report and Findings of Fact Page 8 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 9 of 19
e. Require on-site controls and development standards, as practical, to reduce off-site
impacts from stormwater runoff,
f. Use natural and simple mechanical treatment systems to provide treatment for
potentially contaminated runoff waters,
g. Reduce street-related water quality and quantity problems,
h. Regulate use and require containment and/or pretreatment of toxic substances,
i. Include containment measures in site review standards to minimize the effects of
chemical and petroleum spills,and
j. Consider impacts to ground water quality in the design and location of dry wells.
Finding 10: Stormwater management in Springfield is regulated by multiple programs,
ordinances, and code provisions.Three divisions provide support to the review of stormwater
plans and permits. Long-term stormwater infrastructure planning and development review is
managed by the Community Development Division, stormwater maintenance and enforcement
on private development sites and outreach to the public and property owners are handled by
the Environmental Services Division, and stormwater maintenance of public facilities is the
responsibility of the Operations Division.The Environmental Services Division has a stormwater
public awareness program where they inform residents, businesses, and industries about the
importance of our Drinking Water Protection program and water recreational resources.
Finding 11: The Stormwater Post-Construction Requirements that are included in the code
amendments will improve management of industrial and commercial operations by requiring
structural stormwater controls for any development or redevelopment that disturbs more than
5,000 square feet of impervious surface or one or more acres of land and regulates site planning
for new development, redevelopment, and construction to better manage post-construction
storm runoff in compliance with the MS4 permit. Portions of the Engineering Design Standards
and Procedures Manual (or EDSPM)that apply to private development (such as erosion,
velocity, pollutant loading, and drainage requirements) will be added to the development code.
Construction specifications and design standards that only apply to public infrastructure
approvals or that are non-mandatory guidelines will remain in the EDSPM.
Finding 12: The new code standards will: (1)facilitate and encourage the incorporation of
site-specific management practices that mimic natural surface or predevelopment hydrological
functions, optimizing on-site retention; (2) result in reduced site specific post-construction
stormwater runoff,volume, duration and rates of discharge to the storm sewer system,thereby
minimizing water quality impacts from impervious surface. By increasing the storage, retention,
and natural filtration of stormwater runoff to lower and delay peak storm flows, the stormwater
facilities settle out pollutants prior to discharge to local waterways. (3) encourage the use of
Low-Impact Development or green infrastructure to use natural and simple mechanical
treatment systems that can effectively treat contaminated water quality and quantity issues; (4)
further the intent to capture and treat 100%of the first 1.4" of rainfall or at least 80% of Total
Suspended Solids of whatever portion of the first 1.4"that cannot be captured; and (5)
encourage design techniques that minimize impervious surfaces and again, reduce stormwater
ru noff.
G.14 Implement changes to storm water facilities and management practices to reduce the
presence of pollutants regulated under the Clean Water Act and to address the
requirements of the Endangered Species Act.
Staff Report and Findings of Fact Page 9 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 10 of 19
Finding 13: The amendments to the Springfield Development Code are in compliance with
the City's MS4 Permit. The City is implementing these changes to portions of the stormwater
code requirements to reduce impacts of stormwater runoff on our Drinking Water Protection
areas and local waterways.
G.15 Consider wellhead protection areas and surface water supplies when planning
storm water facilities.
Finding 14: A Stormwater Study is required for the installation of a structural stormwater
control facility. The Stormwater Study must address any impact on wellhead protection areas,
floodplains and floodways, natural resources, wetland and riparian areas, and Water Quality
Limited Watercourses. The amendments to the Drinking Water Protection Overlay District
includes limitations on stormwater facilities in proximity to wellheads that are necessary to
ensure the safety of the city's drinking water supply.
G.16 Manage or enhance waterways and open stormwater systems to reduce water quality
impacts from runoff and to improve stormwater conveyance.
Finding 15: The code amendments manage and enhance the City's waterways and
stormwater systems by:
• Capturing the first 1.4" of rainfall or at least 80% of Total Suspended Solids of whatever
portion of the first 1.4"that cannot be retained onsite. This reduces our stormwater runoff
impact and improves stormwater conveyance;
• Enhancing our water quality and protecting the McKenzie and Willamette rivers from said
runoff helps shield properties and infrastructure from flooding.
G.17 Include measures in local land development regulations that minimize the amount of
impervious surface in new development in a manner that reduces stormwater pollution,
reduces the negative effects from increases in runoff, and is compatible with Metro Plan
policies.
Finding 16: The purpose of these code amendments is to review and update post-
construction requirements for development and redevelopment, especially for project sites that
create or replace 5,000 square feet or more of impervious area and remove barriers to low
impact development and green infrastructure. The amended development code minimizes the
amount of impervious surface in new developments by encouraging the use of vegetated
stormwater facilities or permeable pavements in required landscaping for buildings, parking lots
and parking strips, and open spaces.Amending the code to implement the MS4 permit
requirements for structural stormwater controls not only reduces the negative effects from
stormwater pollution and increases in runoff but is also compatible with the Metro Plan policies.
Conformance with Applicable State Statutes
Finding 17: ORS 197.610 requires local jurisdictions to submit proposed comprehensive plan
or land use regulation changes to the Department of Land Conservation and Development
(DLCD). Notice of the proposed amendments to the Springfield Development Code was provided
Staff Report and Findings of Fact Page 10 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 11 of 19
to DLCD 35 days in advance of the Planning Commission public hearing in compliance with ORS
197.610 and ORS 197.620(3). Therefore,the amendments are consistent with the state statute.
Finding 18: ORS 227.186 requires the local government to mail a notice to every landowner
whose property is proposed to be "rezoned" as a result of adoption or amendment of a
proposed ordinance (also known as "Ballot Measure 56" notice). Rezoning under ORS 227.186
includes an ordinance that amends or adopts regulations that limit or prohibit land uses
previously allowed in the affected land use district. Specifically,the code amendments affect the
"uses" allowed in the Drinking Water Protection Area by prohibiting stormwater infiltration
facilities within 100' of any drinking water wellhead. Because this amendment would prohibit
stormwater infiltration and affect property setbacks, Measure 56 notice is warranted.This
notice was not provided within 21 days of the initial hearing on August 1; however,the notice
issue is cured by continuing the public hearing with the Springfield and Lane County Planning
Commissions until September 5, 2023.
Finding 19: ORS 197.307(4) requires that jurisdictions "may adopt and apply only clear and
objective standards, conditions and procedures regulating the development of housing" and
"may not discourage needed housing through unreasonable cost or delay". The amendments
allow residential development to meet the stormwater management standards through
compliance with the Site Performance Standard in SDC 4.3.110(C)(2).This is a clear and
objective standard requiring on-site retention of the first 1.4"of stormwater, which corresponds
to the 80th percentile storm event. The appendices referenced in SDC 4.3.110 provide clear and
objective design standards for a variety of stormwater facilities that could be used to meet the
Site Performance Standard. Compliance with the site performance standard will not result in
unreasonable costs or delays because (1) it is a requirement that the City must impose under
the MS4 permit, (2) it requires on-site retention of the 80th percentile storm, which is a
reasonable target for development to achieve, and (3) it provides options for treatment facility
types in the code appendices. As permitted in ORS 197.307(6), SDC 4.3.110(C)(2)(b) provides a
discretionary alternative treatment standard if the applicant demonstrates that it is technically
infeasible to meet the Site Performance Standard. ORS 468A.050 requires the City to obtain a
permit from the DEQ in order to discharge any wastes into the waters of the state from any
industrial or commercial establishment or activity or any disposal system, or to construct, install,
modify or operate any disposal system or part thereof or any extension or addition thereto.
Development within the City of Springfield that adds impervious surface results in rainwater
runoff that may be discharged ultimately into state waters of the McKenzie River or Willamette
River in and near Springfield. The City's MS4 permit authorizes the City to continue to convey
stormwater runoff into waters of the state. These development code amendments are required
to be in compliance with the MS4 permit and therefore in compliance with ORS 468A.050.
Conformance with Applicable State-wide Planning Goals and
Administrative Rules
Statewide Planning Goal 1 —Citizen Involvement. To develop a citizen involvement program that
provides the opportunity for citizens to be involved in all phases of the planning process.
Staff Report and Findings of Fact Page 11 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 12 of 19
Finding 20: Requirements under Goal 1 are met by adherence to the citizen involvement
process required by the Metro Plan and implemented by the Springfield Development Code. As
detailed above, a public outreach process occurred during the development code amendment
process. The amendments are subject to the Type IV legislative procedure, which requires public
notification and public hearings before the Planning Commission and City Council. The
procedure has been established by the City and determined to be consistent with the City's
acknowledged Citizen Involvement Program and Statewide Planning Goal 1. The public hearing
notice and hearings before the Planning Commission and City Council and Springfield Oregon
Speaks (Springfield's public outreach website) are recognized as opportunities for citizen
participation. Therefore,the amendments are in compliance with Goal 1.
Statewide Planning Goal 2—Land Use Planning. To establish a land use planning process and
policy framework as a basis for all decisions and actions related to use of land and to assure an
adequate factual basis for such decisions and actions.
Finding 21: This goal outlines the land use planning process and policy framework.The
Metro Plan, Springfield Comprehensive Plan, and Springfield Development Code have been
acknowledged by DLCD as being consistent with the Statewide Planning Goals.The City has
followed the land use planning process and policy framework established in the City's
acknowledged comprehensive plan elements and Springfield Development Code as a basis for
all decision and actions related to the use of land and to assure an adequate basis for such
decisions and actions.
Finding 22: The Stormwater Post-Construction Requirements included in the code
amendments will be adopted by the City Council and Lane County Board of County
Commissioners after the November 6, 2023 Public Hearing. Opportunities have been provided
for review and comment by citizens and local governments.
Finding 23: The amendments originate from the Department of Environmental Quality's
(DEQ) approval of the City's MS4 permit which require the City to regulate post-construction site
runoff and minimize barriers to low impact development and green infrastructure. As stated in
the background, these amendments would allow and encourage the use of stormwater
treatment facilities including swales, rain gardens, and pervious pavements and strengthen
requirements that address stormwater quality issues and improve the quality of water in the
City's drinking water protection areas.
Finding 24: Furthermore,the need for stormwater code updates was addressed in Appendix
F of the Springfield Storm water Facilities Master Plan (Detailed Summary of Recommended
Changes to Standards and Codes).The memorandum identified a number of code changes
needed to meet goals, policies, and implementation actions in the City of Springfield Storm water
Management Plan (2004). They include:
• Up-to-date Standards, With Regional Consistency
• Reduce Impacts of Streets and Parking Lots
• Specifically Allow & Encourage Vegetated Stormwater Facilities in Development Site
Landscaping
Staff Report and Findings of Fact Page 12 of 19
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Exhibit B, Page 13 of 19
• Improve Water Quality Protection Requirements in the Drinking Water Protection
District
• Improve Tree &Vegetation Protection Standards
• Improve Erosion Prevention
• Expand and Fully Implement the LDAP
• [Implement] Maintenance Practices
Staff analyzed these recommendations and the current code to address those implementation
actions that were not already implemented with the 2022 Development Code Update Project or
were in existing code following updates that occurred from 1998 to 2007.
Finding 25: Recommendations that weren't addressed during the previous code
amendments or are required in the MS4 permit are addressed in the Stormwater Post-
Construction Requirements Update including: updating the code to be consistent with regional
standards as recommended by The Springfield Stormwater Facilities Master Plan for infiltration
stormwater quality facilities; allowing and encouraging vegetated stormwater facilities
(including Low Impact Development); improving the water quality protection requirements and
tree and vegetation protection standards; and codifying the maintenance responsibilities and
ownership for stormwater quality facilities. Therefore,the amendments are in compliance with
the MS4 permit and Goal 2.
Statewide Planninq Goal 3—Agricultural Lands. To preserve agricultural lands.
Finding 26: The amendments are for property located within the urban growth boundary of
Springfield and do not affect any land designated for agricultural use. Therefore, Goal 3 does not
apply.
Statewide Planning Goal —Forest Lands. To conserve forest lands.
Finding 27: The amendments are for property located within the urban growth boundary of
Springfield and do not affect any land designated for forest use.Therefore, Goal 4 does not
apply.
Statewide Planning Goal 5—Open Spaces,Scenic and Historic Areas, and Natural Resources. To
conserve open space and protect natural and scenic resources.
Finding 28: The Springfield Development Code is currently acknowledged to be in
compliance with Statewide Planning Goal 5. Pursuant to OAR 660-023-0250(3) local
governments are not required to apply Goal 5 in consideration of an amendment unless the
amendment affects a Goal 5 resource.The amendment would only affect the resource if it:
creates or amends a resource list or portion of an acknowledged plan that protects or addresses
specific requirements of a Goal 5; allows new uses that could conflict with a Goal 5 resource; or
the amendment affects an acknowledged UGB and information is submitted demonstrating that
a resource site is included in the amended UGB area.
Finding 29: The amendments do not create or amend the City's list of Goal 5 resources, do
not allow new uses that could conflict with a Goal 5 resource, and do not amend the
acknowledged UGB. The amendments change code provisions that apply to significant Goal 5
Staff Report and Findings of Fact Page 13 of 19
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Exhibit B, Page 14 of 19
resources that are classified as Water Quality Limited Watercourses (WQLWs) by moving
provisions regarding identification of WQLWs and protection of riparian area functions from SDC
4.3.110 to 4.3.117. However,this change is for code organization purposes only and does not
change the substance of any code requirements or standards that apply to WQLWs.Therefore,
the amendments are in compliance with Goal 5.
Statewide Planning Goal 6—Air, Water and Land Resources Quality. To maintain and improve
the quality of the air, water and land resources of the state.
Finding 30: Goal 6 addresses waste and discharges from development and is aimed at
protecting air, water and land from impacts from those discharges.This goal requires local
comprehensive plans to implement measures that are consistent with state and federal
regulations on matters such as groundwater pollution. Goal 6 does not provide a legal standard
that is independent of what the state and federal water quality programs require, which are
administered by DEQ under the MS4 permit program in this matter. Instead, Goal 6 works in
concert with those standards to ensure that land use planning and regulations prohibit
discharges from development that'threaten to violate, or violate applicable state or federal
environmental quality statutes, rules and standards.'The stormwater amendments do not
authorize any new development or increase intensity of development in way that threatens to
violate state or federal regulations.
Finding 31: The City's MS4 permit requires the City to continue to implement its post-
construction stormwater pollutant and runoff control program. Additionally,the permit requires
that by February 2024,the City's program as it applies to new development and redevelopment
projects will:
1) Implement the use of structural stormwater controls at all qualifying sites that create or
replace 5,000 square feet or more of impervious surface area or disturb one or more acres
of land;
2) Identify, minimize or eliminate ordinance, code and/or development standard barriers that
inhibit Low Impact Development and Green Infrastructure,which is intended to minimize
impervious surfaces and reduce stormwater runoff. Most of the development code
amendments outside of SDC 4.3.110 Stormwater Management reduce barriers to using Low
Impact Development and Green Infrastructure;
3) Implement a site-specific stormwater management approach that targets natural surface or
predevelopment hydrological function through the installation, operation, and maintenance
of structural stormwater controls.The permit allows the City to establish a site performance
standard that is either volume based (for example, capture the first inch of each storm
event), storm event percentile-based (for example,the 95th percentile storm event), or
annual average runoff-based (for example, 80%of annual average runoff).The Site
Performance Standard requiring capture of the first one and four tenths inches (1.4") of
rainfall from each storm event is a volume-based standard that correlates to historical
rainfall data for the Eugene-Springfield area, so that 80%of all storm events will be fully
infiltrated on-site under this standard. If the Site Performance Standard cannot be met due
to site constraints or technical infeasibility,the site must infiltrate as much rainfall as
practicable.The remainder of the runoff up to 1.4" must meet the Treatment Standard to
remove at least 80%of Total Suspended Solids .Review and approve structural stormwater
Staff Report and Findings of Fact Page 14 of 19
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Ordinance No. 6464
Exhibit B, Page 15 of 19
control plans for new development and redevelopment projects for sites that disturb one or
more acres of land and sites that use the alternative treatment standard mentioned above;
and
4) Maintain an inventory and implement a strategy to ensure that all structural stormwater
controls are installed in compliance with the MS4 permit and operated and maintained to
meet the Site Performance Standard mentioned above.
Finding 32: The amendments are necessary to comply with the DEQ requirements in the
City's MS4 permit, which is what is required by Goal 6.Therefore,the amendments are
consistent with Goal 6.
Statewide Planninq Goal 7—Areas Subject to Natural Disasters and Hazards. To protect life and
property from natural disasters and hazards.
Finding 33: Goal 7 requires local government planning program include provisions to
protect people and property from natural hazards such as floods, landslides, earthquakes and
related hazards,tsunamis and wildfires. The Goal prohibits development in natural hazard areas
without appropriate safeguards.The Springfield Development Code is acknowledged to be in
compliance with Goal 7. The amendments do not alter the City's acknowledged land use
programs regarding landslide areas(SDC 3.3.500, Hillside Development Overlay)or flood
protection (SDC 3.3.400).Therefore, the Stormwater Post-Construction Requirements Update
project is in compliance with Goal 7.
Statewide Planning Goal 8—Recreational Needs. To satisfy the recreational needs of the citizens
of the state and visitors, and where appropriate, to provide for the siting of necessary
recreational facilities including destination resorts.
Finding 34: Recreational services within Springfield is the responsibility of Willamalane Park
& Recreation District. Willamalane has an adopted 20-Year Comprehensive Plan for the
provision of park, open space and recreation services for Springfield. This goal is not applicable
to the Stormwater Post-Construction Requirements Update project and the amendments will
have no effect on the availability of or access to recreational opportunities as planned in
Willamalane's Comprehensive Plan. Therefore, the updates are in compliance with Goal 8.
Statewide Planninq Goal —Economic Development: To provide adequate opportunities
throughout the state for a variety of economic activities vital to the health welfare, and
prosperity of Oregon's citizens.
Finding 35: Goal 9 requires the City to "provide for at least an adequate supply of sites of
suitable sizes, types, locations, and service levels for a variety of industrial and commercial uses
consistent with plan policies." The City's adopted Economic Opportunities Analysis and
Commercial Industrial Buildable Lands Inventory is acknowledged to comply with Goal 9. The
amendments do not impact the supply of industrial or commercial lands.
Finding 36: The Stormwater Post-Construction Requirements do not render any property
unusable for commercial or industrial uses. The amendments prioritize the selection of
structural stormwater controls to capture and retain as much stormwater runoff as feasible
Staff Report and Findings of Fact Page 15 of 19
Stormwater Post-Construction Requirements Code Amendments
Ordinance No. 6464
Exhibit B, Page 16 of 19
onsite. Applicants that qualify for the Alternative Treatment Standard due to technical
infeasibility and/or site constraints does not restrict any buildable land area; it merely requires
that development target an equivalent water quality benefit as onsite retention. An applicant
demonstrates technical infeasibility by submitting a report demonstrating that the required size
of the structural stormwater control needed for the development's impervious surface area
would not be feasible or would need to be reduced to meet the Site Performance Standard.
Finding 37: The code amendments retain the existing minimum development areas and broad
categories of uses that are currently allowed in each land use district, which maintains the
existing inventory of sites suitable for a variety of employment uses. Therefore,the
amendments are consistent with Goal 9.
Statewide Planning Goal 10—Housing. To provide for the housing needs of citizens of the state.
Finding 38: Goal 10 requires jurisdictions inventory buildable lands for residential use and
develop plans that encourage the availability of adequate numbers of needed housing units at
price ranges and rent levels which meet the financial capabilities of Oregon households and
allow for flexibility of housing location type and density.The City of Springfield completed a
Housing Needs Analysis and Buildable Lands Inventory in 2011.This document serves as the
City's compliance document under Goal 10 and provides the basis for the City's determination
that Springfield's UGB has sufficient buildable land to meet the identified housing needs during
the 20-year planning period.
Finding 39: The Stormwater Post-Construction Requirements Update amendments do not
conflict with Goal 10 because they preserve the City's inventory of buildable residential lands, by
either not changing or not increasing the overall net density that may be constructed on
residentially designated land.The amendments are more restrictive in terms of how much
impervious surface area can be built before a structural stormwater control is required
(development that creates or replaces 5,000 square feet or more of impervious surface area;
development that disturbs one or more acres of land within the development area; and
development that generates peak flows in excess of 0.5 cubic feet per second within the
development area).
Finding 40: The amendments do not regulate if development can occur, but rather how
development is done. The new regulations:
• Add specific standards for structural stormwater controls to capture the first one and
four tenths inches(1.4") of rainfall from each storm event (Site Performance Standard)
and route the stormwater to one or more structural stormwater controls or if that
standard cannot be met, the remainder of the runoff must be treated to remove at least
80%of Total Suspended Solids (Treatment Standard) (SDC 4.3.110(C)(2));
• Specifically require that any development that cannot meet the Site Performance
Standard in SDC 4.3.110(C)(2) demonstrate that an Alternative Treatment Standard is
proposed due to technical infeasibility or site constraints including but not limited to:
shallow bedrock, high groundwater, protection of groundwater from contamination, soil
instability as documented by a geotechnical analysis, land use that is inconsistent with
capture and infiltration of stormwater, the known presence of soil contamination, or
constraints arising under the provisions of the Drinking Water Protection Overlay
District in SDC 3.3.200. Any structural stormwater controls used to meet the Treatment
Staff Report and Findings of Fact Page 16 of 19
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Exhibit B, Page 17 of 19
Standard must incorporate Low Impact Development(LID)to the maximum extent
practicable (SDC 4.3.110(D)2) and SDC 4.3.110(D)(4));
• Change the City's requirements for Stormwater Study Types to describe how the
proposed stormwater management approach targets the natural surface or
predevelopment hydrologic function of the area through the installation of a structural
stormwater control. It must also address the facilities impact on offsite flows, drainage
areas, environmentally sensitive areas, flood elevations or flood ways, and their
proximity to natural resource areas.
These design requirements do not have a material effect on the density of residential
development. Thus,the amendments do not reduce the development potential of Springfield's
housing land inventories in a manner inconsistent with Goal 10.
Statewide Planning Goal 11 —Public Facilities and Services. To plan and develop a timely, orderly
and efficient arrangement or public facilities and services to serve as a framework for urban and
rural development.
Finding 41: Goal 11 requires the City to plan and develop an efficient arrangement of public
facilities and services to serve urban and rural development. Pursuant to OAR 660-011-0020(2) a
public facility plan must identify significant public facility projects which support the land uses
designated in the comprehensive plan.The Eugene-Springfield Metropolitan Area Public
Facilities and Services Plan (PFSP) and the Springfield 2035 Transportation System Plan (TSP) are
the City's acknowledged public facilities and transportation plans that inform infrastructure
investments (i.e., water, stormwater, wastewater, electricity, and transportation). The TSP is
addressed under Goal 12 below.There are no changes to the PFSP in conjunction with these
amendments, and the project is otherwise consistent with Goal 11 as explained below.
Finding 42: The code updates comply with Goal 11 because they do not result in any need
to amend the PFSP to include additional or different public facilities projects. OAR 660-011-
0045(4) states that"Land use amendments that are those modifications or amendments to the
list, location or provider of, public facility projects, which significantly impact a public facility
project identified in the comprehensive plan and which do not qualify under subsection (3)(a) or
(b) of this rule. Amendments made pursuant to this subsection are subject to the administrative
procedures and review and appeal provisions accorded "land use decisions" in ORS Chapter 197
and those set forth in OAR Chapter 660 Division 18." The amendments do not modify or amend
the list, location or provider of public facility projects identified in the Eugene-Springfield Public
Facilities Plan. Furthermore, OAR 660-011-0020(2) requires the public facility plan to identify
significant public facility projects which support the land uses designated in the comprehensive
plan. Because these amendments will require more onsite retention and treatment than when
the PFSP was written, it will reduce the need for public stormwater facilities in the future as
compared to the prior code.Therefore, the amendments do not change the designations or
categories of any residential, employment, commercial, industrial, or urbanizable lands and are
consistent with Statewide Planning Goal 11.
Statewide Planning Goal 12—Transportation. To provide and encourage a safe, convenient and
economic transportation system.
Finding 43: The Transportation Planning Rule (TRR), at OAR 660-012-0060, requires the City
to adopt mitigation measures whenever "an amendment to a functional plan, an acknowledged
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Exhibit B, Page 18 of 19
comprehensive plan, or a land use regulation (including a zoning map)would significantly affect
an existing or planned transportation facility." An amendment causes a significant effect under
the TPR when it changes the functional classification of an existing or planned transportation
facility, changes the standards for implementing the functional classification system, or results
in any of the effected listed in OAR 660-012-0060(1)(A) - (C) regarding degradation of the
performance of an existing or planned transportation facility.
Finding 44: A land use regulation amendment "significantly affects"transportation under
Subsection 1(a) if it "Change[s]the functional classification of an existing or planned
transportation facility(exclusive of correction of map errors in an adopted plan)."The
amendments do not change any functional classification under OAR 66-012-0060(1)(a).
Finding 45: A land use regulation amendment "significantly affects"transportation under
Subsection 1(b) if it "Change[s]standards implementing a functional classification system."The
amendments do not change the City's standards for implementing its functional classification
system under OAR 66-012-0060(1)(b).
Finding 46: Under Subsection (1)(c), a land use regulation amendment"significantly affects"
transportation if it results in (A) types or levels of travel or access inconsistent with the functional
classification of a transportation facility;(8)degrades the performance of a transportation
facility such that it would not meet performance standards identified in the TSP or
comprehensive plan;or(C)degrades the performance of a transportation facility that is
otherwise projected to not meet the performance standards in the TSP or comprehensive plan.
To determine whether the amendments "significantly affect" a transportation facility within the
meaning of(1)(c) a local government should compare the most traffic-generative use reasonably
allowed in the current zone with the most traffic-generative use reasonably allowed in the new
zone.
Finding 47: OAR chapter 660, Division 12 includes provisions adopted under the"Climate
Friendly and Equitable Communities" rules adopted and certified effective on August 17, 2022,
as amended by temporary rules effective May 12, 2023 through November 7, 2023.These
provisions are either not yet operative for the City of Springfield under OAR 660-012-0012 or
apply only upon amendment to the Springfield Transportation System Plan.Amendments to
Springfield's Transportation System Plan do not accompany the subject amendments, and
therefore the remaining provisions of OAR chapter 660, Division 12, are not applicable.
Finding 48: The amendments do not change the underlying zoning districts or change the
uses that are allowed. Accordingly,the amendments do not change the most traffic-generative
uses allowed and therefore do not result in any of the effects described under (A)-(C).The
amendments to the code will not"significantly affect" an existing or planned transportation
facility under OAR 660-012-0060(1)(a), (b), or(c).Therefore, the amendments are consistent
with OAR 660-012-0060 and Statewide Planning Goal 12.
Goal 13—Energy Conservation. To conserve energy.
Finding 49: The City does not have specific Goal 13 regulations. However, conservation of
water as a renewable energy source is a policy under Goal 13. Goal 13 Policy A. 5. states: "Plans
Staff Report and Findings of Fact Page 18 of 19
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Exhibit B, Page 19 of 19
directed toward energy conservation within the planning area should consider as a major
determinant the existing and potential capacity of the renewable energy sources to yield useful
energy output. Renewable energy sources include water, sunshine,wind,geothermal heat and
municipal,forest and farm waste. Whenever possible, land conservation and development
actions provided for under such plans should utilize renewable energy sources."The code
amendments further Goal 13's policy for energy conservation by prioritizing infiltration,
evapotransporation, and the re-use of stormwater before it is discharged to our public system
or local waterbodies.Therefore,the amendments are consistent with Statewide Planning Goal
13.
Goal 14—Urbanization. To provide for an orderly and efficient transition from rural to urban land
use.
Finding 50: Goal 14 requires cities to estimate future growth rates and patterns, and to
incorporate, plan, and zone enough land to meet the projected demands.The amendments do
not affect the existing code provisions regarding the transition of land from rural to urban uses
or annexation.The code provisions regarding urbanizable land are contained in the Urban Fringe
Overlay District and the Agricultural Urban Holding Area district. There are no amendments to
these sections or standards.Therefore, the amendments are consistent with the requirements
of Statewide Planning Goal 14.
Goal 15—Willamette River Greenway. To protect, conserve, enhance and maintain the natural,
scenic, historical, agricultural, economic and recreational qualities of lands along the Willamette
River as the Willamette River Greenway.
Finding 51: Statewide Planning Goal 15 requires cities to adopt local greenway plans, along
with criteria for new development or uses along the river. Pursuant to SDC 3.3.320(A), uses
allowed in the Willamette Greenway Overlay District are the same as those in the underlying
zoning district; thus the Stormwater Post Construction Requirements Update amendments do
not repeal, replace, or void these existing code provisions related to Goal 15. Furthermore,
there are no changes to the existing overlay protections from this amendment. Therefore,the
amendments are consistent with the requirements of Statewide Planning Goal 15.
Goal 16—19 Estuarine Resources, Coastal Shorelands, Beaches and Dunes, and Ocean Resources.
Finding 52: Statewide Planning Goals 16—19 relate to coastal lands in Oregon, which are
not applicable within the planning jurisdiction of the City of Springfield and are not applicable to
the amendments.
VI. CONCLUSION
Based upon the evidence above and the criteria of SDC 5.6.115 for approving amendments to
the Springfield Development Code,the text amendments to SDC 4.3.110 and various other
sections for stormwater management are consistent with these criteria.
Staff Report and Findings of Fact Page 19 of 19
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